By: Dr. David H. Menke v 1 - Continental · PDF fileSurvey of Physical Sciences 7 LESSON 1 -DIRECTION OF TIME AND SPACE Time Clocks, watches, and other devices called “chronometers,”

Survey of Physical ScienceSurvey of Physical ScienceBy: Dr. David H. Menke

v 1.0By: Dr. David H. Menke

v 1.0

Survey of Physical Sciences

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I N S T R U C T I O N S

Welcome to your Continental Academy course “Survey of the Physical Sciences”. It is made up of 9 individual lessons, as listed in the Table of Contents. Each lesson includes practice questions with answers. You will progress through this course one lesson at a time, at your own pace. First, study the lesson thoroughly. Then, complete the lesson reviews at the end of the lesson and carefully check your answers. Sometimes, those answers will contain information that you will need on the graded lesson assignments. When you are ready, complete the 10-question, multiple choice lesson assignment. At the end of each lesson, you will find notes to help you prepare for the online assignments. All lesson assignments are open-book. Continue working on the lessons at your own pace until you have finished all lesson assignments for this course. When you have completed and passed all lesson assignments for this course, complete the End of Course Examination. If you need help understanding any part of the lesson, practice questions, or this procedure:

Click on the “Send a Message” link on the left side of the home page

Select “Academic Guidance” in the “To” field Type your question in the field provided Then, click on the “Send” button You will receive a response within ONE BUSINESS DAY


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About the Author…

Dr. David H. Menke was born and raised in the St. Louis area. After high school, he enrolled at the University of California at Los Angeles, and over the next eleven years, earned his two bachelor’s degrees, his four master’s degrees, a teaching credential, and a Ph.D. in Science Education. During his career, Dr. Menke has served as a public school teacher, community college instructor, and university professor. He has worked full time at such institutions as California State University, Northridge; Southern Utah University; Central Connecticut University; and Broward Community College. Much of his career was spent as an academic administrator of public observatories and planetariums. Dr Menke serves as the First Vice-President and COO of the International Planetarium Directors Congress, and as Chief Astronomer for the Sossusvlei Mountain Lodge in Namibia, Africa. As a world traveler, Dr. Menke has served as leader of many expeditions, including observations of eclipses and comets – on land and at sea. Dr Menke speaks, reads, and / or writes 16 languages. Dr Menke is married and has six children ranging in age from 7 to 28. He also has 4 grandchildren. Dr Menke’s wife is an elementary school teacher and mental health counselor.

Survey of the Physical Sciences SC 10 Editor: Barry Perlman

Copyright 2008 Home School of America, Inc.

ALL RIGHTS RESERVED

The Continental Academy National Standard Curriculum Series

Published by:

Continental Academy 3241 Executive Way Miramar, FL 33025


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Physics and chemistry; particularly mechanics, the laws of motion, energy, the elements, molecules, atoms, sub-atomic particles, nuclear reactions, light, heat, the periodic table, and chemical changes are introduced. Astronomy, Geology and Meteorology are surveyed. Each of the 9 lessons is 10 – 20 pages long with many examples and practice assignments. A laboratory exercise is part of several of the lessons. There is a 10-question assignment (which will be graded) upon the completion of each lesson. There is a 50-question assignment upon the completion of this course.

Student should develop an understanding of the structure of the

atom

Student should develop an understanding of the structure and

properties of matter

Student should develop an understanding of chemical reactions

Student should develop an understanding of motions and forces

Student should develop an understanding of conservation of energy

Student should develop an understanding of interactions of energy

and matter

Student should develop abilities and understandings about scientific

inquiry

Student should develop an understanding of natural resources

Student should develop an understanding of environmental quality


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TABLE OF CONTENTS

Lesson 1-- The Direction of Time and Space…………………………………7 Lesson 2-- Measures and Motion……………………………………………..19 Lesson 3 - -Energy……………………………………………………………...35 Lesson 4 -- Heat and Waves…………………………………………………..47 Lesson 5 -- Electromagnetic Radiation……………………………………….69 Lesson 6 -- Building Blocks and Nuclear Energy…………………………....79 Lesson 7 -- Chemical Elements………………………..…………………….. 91 Lesson 8 -- Chemical Changes………………………...…………………. 105 Lesson 9 -- Other Physical Sciences .......................................................115 End of Course Review .......................................................................... 137


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LESSON 1 - DIRECTION OF TIME AND SPACE

Time Clocks, watches, and other devices called “chronometers,” or

“chronographs,” or timepieces measure time. The word “clock” comes from

the Latin word clocca, which means “bell.” In olden days, a clock

tower would ring a bell every hour. The Greek word krono

means, “time” and a meter measures, while a graph records.

Therefore, any timepiece may be referred to as a chronometer or

chronograph. The word “watch” comes from an old English phrase,

waeccan, which means “watchable,” or “worth watching” or “worth looking

at.” In nautical, Greek, and Roman terms, a person’s “watch” meant his

“period of being on duty.” Therefore, we measure out time with a small

timepiece called a watch.

The basic unit is the second, and there are 60 seconds in a minute.

Coming from the Latin word, secundum, which means “division of time,”

we divide an hour into minutes and seconds. One might expect that the

word “minute” would also come from Latin, and it does. Minuta in Latin

used to mean “very small division of time.” Of course, a second is even

smaller.

The length of the second probably came about

since the human heart beats approximately 60

times in one minute – or once per second. Thus,

our measurement of time is based upon a natural

biorhythm.


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Example Try this simple experiment. Use a watch or clock to determine your

heartbeat rate. Find your pulse (using your wrist or in your throat area), and

then count the number of pulses during a 60-second period. When a

person gets nervous or afraid, the pulse rate goes up. If your pulse rate is

very high, you may wish to consult a physician.

Time Zones Earth is a sphere, and as such, has a circumference of 360 degrees – just

like a circle. Scientists divided these 360 degrees into 24 different time

zones, each approximately 15 degrees (1,000 miles) wide. The time zones

begin in Greenwich, England, at 0 degrees, and increase by one hour of

time for each 15 degrees eastward. Also, the time decreases one hour for

each 15 degrees westward. Before Time Zone Laws went into effect, each

town, village, and city had its own time, based upon the position of the Sun.

Example In the old days, when each town had its own time, the time might be 12:10

PM in Boston, Massachusetts, while in Hartford, Connecticut it would be 12

Noon, and in New York City, it would be 11:50 AM.

Now that time zones have been “standardized,” it means that the clocks in

every town and every city within the same time zone have the same time.


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Examples Every town from Bangor, Maine to Miami, Florida, is in the same time zone.

This is called the Eastern Time Zone or Greenwich Mean Time minus 5

hours. The continental United States has 4 time zones: Eastern, Central,

Mountain, and Pacific. Of course, when one includes Alaska and Hawaii,

that adds more time zones to the U.S. Canada has 5 time zones – 4 that

are exactly the same as those in the continental U.S., and 1 more – a time

zone for the Maritime Provinces of Nova Scotia, Prince Edward Island, and

New Brunswick. These provinces are east of the Eastern Time zone, and

are in the Atlantic Time zone, which is one hour ahead! Canada’s Maritime

Province of Newfoundland has its own time zone, one-half hour ahead of

the Atlantic Time Zone.

Although England is in the Greenwich time zone, most of Western Europe

is one hour ahead – except for Portugal. So, Spain is one hour ahead of

Portugal!

Daylight Savings Time

Daylight Savings Time (DST) is a plan for setting clocks 1 (or 2) hour(s)

ahead so that the sun both rises and sets at a later hour. This gives an

additional hour of daylight in the evening – used mostly during summer

months.

The American Statesman Benjamin Franklin first introduced Daylight

Savings Time in 1764. Later, a Briton, William Willett, advocated it in 1907.


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Daylight Savings Time (DST) has since been used in the United States and

in many European countries since.

During World War I, DST was adopted in order to save energy. Some

places returned to standard time after the war, but others kept DST.

The U.S. Congress passed a law during World War II that placed the entire

country on “war time,” which set clocks 1 hour ahead of standard time.

“War Time” was also followed in the United Kingdom, and clocks were put

ahead 2 hours during summer months.

In peace time, DST was controversial. Farmers were inconvenienced when

they had to conduct business on a different time schedule. Railroads, bus

companies, and airline companies had scheduling problems due to

inconsistencies in various cities and states. In 1966,

Congress passed a law called The Uniform Time Act. It established a

system of uniform daylight saving times throughout the states, exempting

only those states in which the state legislature voted to keep the entire

state on standard time. The states of Arizona and Hawaii do not have DST;

parts of Indiana also do not have DST.

Since 2007, DST begins at 2 AM on the second Sunday of March and ends

at 2 AM on the first Sunday of November.

But what is time and what is its purpose? In the science of relativity -

discovered by Albert Einstein - we say that “time separates events in


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space.” In other words, if we were to observe a specific location in the

universe for a while, we might notice a variety of “events” occurring over

time. The only thing that separates these “events” is time itself.

Example A simple example might be a classroom in any school. Let’s say that Mrs.

Jones has a 1st period class in the

subject of English, every weekday

during the school year. Let’s say

that 1st period runs from 8:00 AM to

8:55 AM. Let’s also say that Mrs.

Jones has a 2nd period class in

another subject, like Creative

Writing, and it runs from 9:00 AM to 9:55 AM.

Let’s also say that Mrs. Jones holds these two classes in the exact same

room, Room 202. Thus, Room 202 is defined as a “space.”

Each school day there are many distinct “events” in that space (in Room

202). Event 1 is a lesson in English with a certain group of students. Event

2 is a lesson in Creative Writing with a completely different group of

students. Event 3 may be an “empty” classroom with nothing going on, and

so forth. Perhaps that would be Mrs. Jones’ planning time.

The only thing that separates these three events (the two groups of

students and the planning period) is Time. The space is the same. The

teacher is the same. If time had no meaning, or did not exist, then we might


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expect anything and everything happening in this space in any order. That

would be “chaos” – another branch of physics.

Time is an entity measured by timing devices called chronographs or

chronometers. These include clocks, watches, and other similar tools,

including candles and sundials.

Time always moves forward into the future coming from the past, and is

always in the present. Time never moves backwards, except in science

fiction. Therefore, we refer to time as being one-dimensional.

While time is measured in units of seconds, there are also many other units

of time, developed for convenience, such as minutes, hours, days, weeks,

months, years, decades, centuries, millennia, and eons. We can also divide

the second into milliseconds, microseconds, and even smaller units.

Space

While we often refer to the word “space” when talking about stars and

galaxies, out in “space,” in reality, “space” is a far more important concept.

While Time is one-dimensional, Space, on the other hand, is three-

dimensional, or 3-D. An artist or an architect would explain space as,

“height, width, and depth.” Height is the up and down dimension,

sometimes called “the y-axis.” Width is the left and right dimension,

sometimes called “the x-axis.” And, finally, depth is the in and out (or


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Y

X

Z

-X

-Z

-Y

backwards and forwards) dimension, often called “the z-axis.” We can go

up and down, left and right, backwards and forwards.

Space has the units of length, width, and

height, or volume. In science, volume is

in the units of liters. Remember that 1000

mL = 1000 cc = 1000 cm3 = 1.0 liter. This

would be the volume of a cube with a

length of 10 cm, width of 10 cm, and height

of 10 cm. When we use only two axes (we pronounce this word “ax-eez,”

so as not to confuse it with the plural of a tool called an “ax”) say, the x-axis

and the z-axis, then that entity is called a “plane.” Don’t confuse this with an

airplane or a field, like a plain in Kansas. The entity is just a “plane.” The x-

z plane is a two-dimensional flat surface – such as a horizontal tabletop.

The top of a table is two dimensional or 2-D. The wood of the tabletop

itself has thickness, and thus, has components that are three dimensional

or 3-D and into the y-axis. But, in this case, we are referring only to the

surface of the table. The surface of a sheet of paper is also 2-D.

While science fiction often talks of 4 or 5 dimensions of space, we humans

cannot grasp what that may be. Even so, human scientists such as the late

Carl Sagan often discussed the possibility of such dimensions, and how

interesting they may be.

Thus, for now, we recognize only four dimensions: the 1-D of time, and the

3-D of space. We call this “the fabric of space-time,” and it will come up

later.


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Key Terms and Concepts units of time

units of space

fabric of space time

definition of time

definition of space Problems 1. Which statement is true about the many time zones around the globe?

a) Each time zone has the same width.

b) Every time zone has a different length.

c) There are 12 time zones around the globe.

d) It is the same date everywhere in the world.

2. Which statement is true about the history of Daylight Savings Time?

a) It started with Ben Franklin, then never changed.

b) It has never been used in wartime.

c) It has never been accepted by the government.

d) Its start and end dates changed in 2007.

3. Where on Earth is it exactly 12 hours ahead of where you live?

a) 12o East c) half-way around

b) b) 12 hours East d) all of the way around

4. What can we call a timepiece?

a) chronograph c) either a chronograph or chronometer

b) chronometer d) a timeometer


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5. How many times does the human heart beat per minute?

a) 30 b) 40 c) 20 d) 60

6. How many degrees is each time zone is divided into?

a) 15 b) 20 c) 120 d) 90

7. England is in which time zone?

a) Forward b) English c) Greenwich d) Eastern

8. Who first introduced Daylight Savings Time?

a) George Washington

b) George Takai

c) George Wahl

d) Benjamin Franklin

9. In three dimensions, which set of axes is used to define space?

a) x,y,z b) y,e,f c) x,y,t d) x,q,r

10. How many liters are 1,000 ml?

a) 5 b) 10 c) 1 d) 100

Answers 1. There are 24 times zones around the globe, each approximately 1,000

miles wide in longitude. Choice a. The zones start with Greenwich,

England (at 0 degrees) and increase one hour per time zone as one

moves eastward, and decrease one hour per time zone as one moves


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westward. The International Dateline, which is on the opposite side of

the world from Greenwich at 180 degrees, marks the separation of one

day from another. For example, just west of that line it may be

Wednesday, while just east of that line would still be Tuesday.

2. The history of Daylight Savings Time started with Ben Franklin, then was

brought up by a British scientist, then later used in World Wars I and II.

Eventually our current system was enacted in 1986 and changed in

2007. Choice d.

3. On Earth the place that is exactly 12 hours ahead of the Eastern Time

Zone is in Southeast Asia (Thailand, Indonesia, etc.) Choice c.

4. c Either term may be used

5. d About 60 times a minute

6. a About 15 degrees each

7. c The Greenwich Time Zone

8. d Benjamin Franklin himself

9. a x,y and z

10. c One liter by definition


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LESSON 1 THINGS TO REMEMBER

Daylight Savings Time was introduced during WWI

If the time is12 Noon in New York City it is 12 Midnight in Bangkok,

Thailand

If the time is12 Noon in New York City, it is 12 Noon in Miami

A chronometer is the device that indicates time

There are 24 time zones around the globe

There are 3600 seconds in an hour

Time is one-dimensional and space is 3-D

A photographic image is two-dimensional

A natural biorhythm is the human heart (at rest) beating about

once per second Two liters of soda filling a plastic bottle measures that soda’s

volume


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LESSON 2 - MEASURES AND MOTION

In the physical sciences, we are continually measuring things. The basic

measurements include length (or distance) and mass (or weight). We

measure lengths with rulers, meter sticks, measuring tapes, and various

other tools, including micrometer calipers for very short distances.

In science, the standard unit of length is the meter. A meter is about 39

inches, 3 more inches than a yard. However, a meter is defined as part of

the Earth itself: the distance from the equator to the Geographic North Pole

is exactly 10 million meters.

The “yard” was the distance of a British

king’s arm, so we don’t find that very

scientific. The yard is also equal to three

feet, presumably the typical person’s foot

length. The confusion that exists within this

system of measurement can be illustrated

with the following example. “Yards” and “feet” were developed as social

conventions to standardize measurements and thus facilitate trade.

Example There’s a story of a grandma sitting on a

porch and knitting 3 socks. “Why are you

knitting 3 socks?” asked a neighbor. “Well,

my grandson told me that he has grown a

foot since he’s been in the Army!”


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Of course, there are units larger and smaller than the meter. For example,

100 centimeters is equal to 1 meter. This is just like 100 cents are equal to

1 dollar. As a comparison, 2.54 centimeters equals 1.0 inch, and 12 inches

equals one foot.

And 1,000 millimeters is the same as 1 meter. Although not used in society

any more, there used to be coins

called mills that were 1/10th of a

cent. A total of 1,000 mills

equaled 1 dollar. People used

these mills in the old days to pay

taxes when the tax on some item

was less than a penny. Most mill

coins were made of plastic.

On the other hand, 1,000 meters

is equal to 1 kilometer, from the word kilo, which means “thousand.” As a

comparison, 1.6 kilometers equals 1.0 mile, or 1.0 kilometer is about 5/8th

of a mile.

People who study the physical sciences use units as small as a nanometer,

an Angstrom, a picometer, and other tiny units; and they use units as large

as megameters, light years, parsecs, and kiloparsecs. In your study of the

physical sciences, you will run across these terms.

Now, one may ask, “What is wrong with inches, feet, yards, and miles?”

Well, nothing really. But science likes to use units based upon constants,


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not on the length of the arm of the local king. Plus, one may notice that all

the metric units are in powers of ten. This decimal system is much easier

to use than the old English standard system.

As another thought, realize that 12 inches equals a foot (not 10 inches), 3

feet equals one yard, and 5,280 feet equals one mile. The decimal system,

usually called the metric system, is not complicated or confusing at all

because it’s based on multiples of ten.

When we measure the weight, or mass, of an object, we again use units in

the metric system. For example, the unit of mass is

the kilogram – or 1,000 grams. Each kilogram

weights about 2.2 pounds at sea level on Earth. But a

kilogram, or a gram, measures mass, not weight.

Mass never changes over time or space, while weight

is really a force, and it is different at each place in

space.

Example If you weighed 120 pounds on Earth, you’d weigh only 20 pounds on the

Moon. You wouldn’t be thinner, or look any different, but the force of the

Moon’s gravity on you (your weight) would be less. However, if you were 55

kilograms (120 pounds) on Earth, you’d still be 55 kilograms on the Moon,

or anywhere else.

Mass is merely the amount of matter, not how the matter is affected by a

gravitational force field. For convenience, we often say that 1.0-kilogram


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equals 2.2 pounds. But what we really mean is that a 1.0-kilogram object

weighs 2.2 pounds at sea level on the planet Earth.

Example How much is your mass? Find a

bathroom scale, “weigh” yourself,

and divide that number by 2.2. This

will give you your own mass (in

kilograms).

In sum, we scientists use the units

of seconds, meters, kilograms, and other related measurements.

If an object is NOT moving at all, then it has a set of coordinates, i.e., a

place in space that is identified with a particular value for EACH of the x, y,

and z coordinates (recall the conclusion of Lesson 1).

Example The city of Ft. Lauderdale, Florida, has a set of coordinates that pinpoints

its position on Earth. These are called the latitude and longitude of this

position. Ft. Lauderdale is approximately 26 degrees north and 80 degrees

west. This means it is 26 degrees north of the Equator, and 80 degrees

west of Greenwich, England. The “z coordinate” would be elevation (feet

above sea level) of 6 feet.

However, very few objects are merely stationary. Even Ft. Lauderdale is

moving – relative to space. Although it is fixed on Earth’s surface, Earth is


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rotating (spinning) at about 1600 kilometers per hour (about 1,000 mph).

Plus, Earth is revolving around the Sun, at about 30 km/sec (about 20

miles/sec). Thus, even though the city of Ft. Lauderdale is not wandering

around Earth’s surface, it is still in motion.

Thus, any and every object is moving. And if it is moving, then it has a

speed, or velocity. It may also

have acceleration; which is

velocity.

The speed of an object is a

measurement of how fast it is

going – usually relative to Earth’s

surface. For example, one may

drive his car at 60 miles per hour. This is the car’s “speed”, which is the

distance traveled over the period of an hour (assuming that the speed is

always at 60 for the entire hour). However, in the physical sciences, we are

more concerned about meters per second.

The fastest speed anything can go is the speed of light, often symbolized

by the letter “c.” Light travels at the incredible speed of about 300,000

kilometers per second, or 300 million meters per second (about 186,282

miles per second). At this amazing speed, one could travel around Earth

seven times in one second, to the Moon in 1¼ second, to the Sun in 8

minutes, to Pluto in 5 hours, and to the nearest star outside of the sun in

just over 4 years.


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Even so, the speed of light is not infinite, as Galileo first believed. Thus,

everything else in the universe travels slower than the speed of light.

Example So, let’s imagine that you are driving a car down the highway at a speed of

60 miles per hour. Let’s change that into kilometers per hour: 60 miles is

equal to 96 kilometers. Thus, the speed is 96 km/hr. How fast is that in

kilometers per second? There are 3600 seconds in an hour, so 96 km/3600

seconds equals 0.0267 km/sec, or 26.7 meters/second.

In the physical sciences we are more interested in velocity, than speed.

You might ask, “Isn’t it the same thing?” Yes, and no! Both measure how

fast something is going. But velocity also includes the direction that the

object is going.

Example A speed may be 60 miles per hour (or 26.7 meters per second), but a

velocity would be 60 miles per hour north (or 26.7 meters per second

north). Notice that a direction is added on to the speed to make it a

velocity. That’s really the only difference between speed and velocity. Or,

speed + direction = velocity.

Once we add direction and speed, then the entity becomes a vector. A

vector is like an arrow. No competent archer or woodsman would shoot an

arrow at random. He or she would shoot the arrow towards an object,

whether a deer or an enemy.


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Airline pilots also use the term “vector” to describe the speed and direction

that their airplanes are flying.

Acceleration Now let’s talk about acceleration. Pretend that you are in a car, and you are

ready to pull out of the driveway onto the street. In order to make your car

“go,” you will have to step onto a floor pedal called the “accelerator.” You

would never step on the brake pedal or some other pedal in order to “go.”

But why is this pedal called the “accelerator” (also known as the “gas

pedal”)? Because when you push this pedal, the automobile speeds up –

i.e., it changes its speed. When you push down on the accelerator, you car

speeds up, or, in other words, you accelerate.

Example The term “acceleration” means that you are changing the velocity, over

time. You may be traveling at 30 miles per hour north, but then choose to

speed up to 50 miles per hour north. That means that you will have to

increase your velocity from 30 miles per hour north to 50 miles per hour

north – or a difference of 20 miles per hour north. And how long will it take

you to do that? Let’s say it takes 10 seconds. Then you will have an

acceleration of 20 mph/10 sec = 2 mph/sec north.

In the physical sciences, we don’t use the units of miles per hour per

second. Rather, we use meters per square second. No, there is no such

thing as a “square second” like there is a unit called “square feet.” But it is a

term that we use meaning seconds per second. Instead of 2 miles per hour


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per second north, we’d say so many meters per second per second (0.89

m/sec/sec) north, or, for convenience, 0.89 meters per second squared

north. We also would write it 0.89 m/s2 north. It’s just a phrase we use for

convenience.

So, in summary, distance is measured in meters, such as length along the

x-axis. Speed or velocity is distance (in meters) per second, such as

meters/second, or v = x/t along the x-axis, where “t” is the time in seconds.

Acceleration is the change of velocity over time, or (v/t) = (x/t)/t = x/t2. Note

that here “v” represents the change in velocity. Acceleration is the change

of velocity over time. Remember, velocity is speed plus direction. So, if an

object’s direction of motion changes, but its speed does not, that object still

is accelerating. How can this be? This occurs whenever an object’s

motion follows a curved path without speeding up or slowing down.


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Physical Science Lab

I Title: Density of Water

II Purpose: To determine the density of tap water; to learn the proper

scientific method for lab reports; to get used to measuring.

III Equipment Needed

1 - Small glass tumbler

1 – Measuring cup

Scale that weighs ounces of solid food

Tap water

Pen, calculator, lab book, etc.

IV Procedure

1. "Weigh" the empty, dry measuring cup on the scale. Record the answer

in fractions of an ounce. (e.g. 3.5 oz.) [Record all data in Section V (Data

& Calculations) below.]

2. Pour exactly ¼ cup water in measuring cup.

3. "Weigh" the measuring cup with the water in it. Record the answer in

fractions of an ounce.

4. Find the "weight" (i.e., mass) of the water in ounces, and record this. Do

this by subtracting the weight of the dry cup from the one filled with

water. Convert ounces to grams.


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5. Find the density of tap water, by dividing the mass of the water by the

volume of the water 59.15 mL (see below) or (. Give the answer in

grams per milli-liter (mL), which is the same as grams per cubic

centimeter (cc). Record this answer. (Do all calculations in Section V

below). Conversion: ¼ cup water = 2 fluid ounces = 59.15 mL = 59.15

cc.

Conversion: 1.0 pound = 453.6 grams

V. Data & Calculations 1. Mass of dry measuring cup (in fractions of an ounce)

____ oz. ______ grams

2. Mass of cup plus ¼ cup (59.15 mL) of water

_____ oz. _________ grams

3. Mass of the water (subtract #1 from #2)

_________oz. _________ grams

4. Density of the water (Divide #3 by 59.15 mL)

________________ grams/mL

VII Error Analysis A. Random Errors are ones that you can’t control. However, if you repeat

the experiment several times, all random errors will cancel out

B. Systematic Errors are caused by faulty equipment or from faulty logic

when performing the experiment

C. Personal Errors are caused by the experimenter himself/herself

D. Quantitative Error

The true answer is one gram per cubic centimeter = 1.0 gram/cc =

1.0 g/ml. To find out your percent error (%), here is what you do:


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1. Subtract your answer from the true answer. Then take the positive

difference of that (if the answer is positive, good, if it is not, make it

a positive number by removing the negative sign) or

| True answer – Your answer | = _________ 2. Divide this number by the True answer: | T - Y | / T = __________

3. Multiply this number by 100, converting it to a percent (include the

percent sign = ________

E. Qualitative Error

1. Is your answer correct to within 10%? If so, good job, and

congratulations!

2. However, if your answer is more than 10% off, please list some

things that you would tell another experimenter to do (or not do) to

make the answer have a smaller error. In other words, what do

you think contributed to the error?

3. Is your answer more than 100% off? Please do the experiment

again.

VIII Questions (answer from your experiment, or from books, Internet, or

other sources.

1. What is the density of ocean water (salt water)? Is that more, or less,

than the density of tap water?

2. Is it easier for a human to float in the ocean or in a fresh water lake?

Explain why or why not.


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3. Is solid water (ice) denser, or less dense, than liquid water? Explain.

4. How many gallons of water are there on planet Earth?

Key Terms and Concepts

metric system powers of ten speed

mass motion velocity

weight rotation meters per second

length revolution acceleration

units in the old system meters

units in the metric system

meters per square second

Problems 1. Convert 5-foot, 10-inches into centimeters

a) 5.1 cm b) 15 cm c) 27.6 cm d) 177.8 cm

2. Convert 200 pounds into kilograms (on Earth)

a) 0.200 kg b) 33.3 kg c) 90.9 kg d) 440 kg

3. How many grams are in a kilogram?

a) 0.001 g b) 1.00 g c) 1,000 g d) 1,000,000 g


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4. How did we get the unit of the “yard”?

a) The width of the front yard of the King’s castle.

b) 100 yards is the distance from the first hole to the second hole on

Scotland’s first golf course.

c) 1,000 yards is the width of every time zone.

d) One yard is the length of some king’s arm.

5. Assume that the equator of the Earth is 24,000 miles long (that’s its

circumference). Now, pretend that you are standing somewhere on the

equator, such as in the country of Ecuador. Now, if the Earth turns once,

completely, in 24 hours, then how fast would you be going, even if you

just stood still?

a) 1,000 miles per hour b) 240 mph c) 24 mph d) 0 mph

6. If your Aunt Mary lived 100 miles from you (by car), how fast should you

drive your car (on average) to get to her house in 2 hours? 90 minutes?

1 hour?

a) 100 mph 100 mph 75 mph

b) 50 mph 67 mph 100 mph

c) 25 mph 50 mph 50 mph

d) 10 mph 25 mph 10 mph

7. Now, imagine that you take a road trip of 80 miles, from A to D, but you

have to do it in segments. Let’s say you drive from A to B in 30 minutes,

B to C in 45 minutes, and C to D in 15 minutes. The distance from A to B

is 15 miles; from B to C is 45 miles, and C to D is 20 miles. How many

miles did you drive from A to D? How many minutes did it take you to


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drive from A to D? Convert all those minutes into hours, by dividing by

60 – how many hours did it take you to drive from A to D? What was

your average speed during your trip from A to D?

miles minutes hours mph

a) 80 90 1.5 53

b) 80 90 1.0 80

c) 53 80 60 0.88

d) 80 80 1.3 13

8. A racecar driver speeds up from 60 miles per hour to 90 miles per hour

in 3 seconds. What was his/her acceleration?

a) 30 mph b) 30 mph/s c) 4.44 m/s2 d) 16 km/h

9. One meter is equal to how many millimeters (mm)?

a) 100 b) 1,000 c) 10 d) 100,000

10. The speed of light (c) is the speed limit for the universe.

a) True b) False

Answers 1. d 3. c 5. a 7. a 9. b

2. c 4. d 6. b 8. c 10. a


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5-foot, 10 inches is equal to 178 centimeters

200 pounds is equal to 91 kilograms

There are 1,000 grams in a kilogram

The unit of a “yard” was the length of a British King’s arm

Assume that the equator of the Earth is 24,200 miles in

circumference. Now, pretend that you are standing somewhere on

the equator, such as in the country of Ecuador. Now, if the Earth

turns once, completely, in 24 hours, then you would be going, in miles

per hour, 1,000 even if you were standing still

If a person lived 100 miles from you (by car) how fast (miles per hour)

should you drive (by car) to get to that person’s house in 2 hours (100

miles divided by 2 hours would give you 50 miles per hour speed.)

To solve certain types of driving distance and average speed

problems, first add up the miles driven then divide by the hours driven

to get the average speed. (Suppose you drive 840 miles in 12 hours,

what is your average speed? 840 miles/12 hours = 70 miles per

hour.)

Your weight on Earth is greater than your weight on the moon. And

your weight on the moon would be less than your weight on Earth

One pound of solid water is less dense then one pound of liquid water


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35

LESSON 3 - ENERGY Momentum In Latin, the word momentum means “moving power.” In the physical

sciences, momentum is quite simple; in a way, it is the energy of motion.

Here, it’s the mass of an object multiplied by its velocity (therefore, it has a

direction, and is a vector). Momentum is symbolized by the letter “p,” so p =

m x v, where “x” means “multiplied by.” Here, “v” stands for velocity, not a

change in velocity.

“s

mkg − ”

Example If a 1.0-kilogram object were traveling north at 30 m/s, then the momentum

would be 1 x (30) = 30 kg-m/s.

A slow moving bowling ball has a mass of 10 kilograms and a fast moving

marble has a mass of only 10 grams = 0.01 kg. Each would have the same

momentum if the bowling ball was traveling at 10 m/s and the marble was

traveling at 10 km/second! A fast moving marble can pack a wallop! It is

similar to a bullet, which weighs almost nothing, but travels about 500

meters/second.

In society, we often use the term “momentum” to mean

the energy of motion of a person or a cause. For

example, in 1991 and 1992, Bill Clinton, then-

governor of Arkansas, was able to develop political

“momentum” that propelled him into the White House.


36

At first, nobody believed that he had a chance, but he never gave up, and

his momentum was so great, in the end, nobody could stop him.

Force

The Latin word fortis, which means “strong,”

evolved over time to become the word “force.”

Isaac Newton, a British scientist, spent much

of his life studying force. In fact, Newton developed the Three Laws of

Motion, which included the concept of force. Newton was a rare kind of

thinker; he was a genius.

Originally, the first Laws of Motion were discovered in the year 330 BC by

the Greek thinker, Aristotle, who stated:

1. Objects in motion come to rest

2. Objects that go up, must come down

Later, in the early 1600’s, both astronomers Johannes Kepler (a German)

and Galileo Galilei (an Italian) also studied these laws. In the late 1600’s,

Newton developed three, not two, laws:

1. Objects in motion stay in motion, unless an unbalanced external

force is applied.

2. The amount of force needed to accelerate an object is equal to the

mass of an object multiplied by its acceleration, or F = m x a. 3. Every action (force) has an equal and opposite reaction (or force).


37

This brings us to the concept of force. As defined above, a force, F, applied

to an object of mass, m, would then accelerate the object at a rate of a.

Necessarily, if the mass is very, very high relative to the force, then the

acceleration will be very, very small, perhaps even close to zero. For

example, if a human exerts a force on a huge concrete building, it won’t

move; thus its acceleration is, zero.

Example You already know that distance is measured in meters, but you may not

know that force is measured in units called Newtons. Since much of

Newton’s work dealt with the laws of force, the unit of force was named a

“Newton,” in his honor. The Newton is equal to kg-m/s2. Thus, we define

1.0 Newton = 1.0 N = 1.0 kg- m/s2. When a baseball pitcher, or a football

quarterback, or any other such player exerts a force on a ball, it leaves the

hand and quickly accelerates to a maximum speed.

The planet Earth exerts a force on all objects near it. This is the

gravitational force. The force of gravity is equal to the mass of the object

(such as your mass) multiplied by the acceleration due to the gravity of the

planet; in this case, it’s Earth.

You can find out the acceleration of gravity very simply using a piece of

string, a metal washer, a ruler, and a stopwatch. As it turns out, the

acceleration due to gravity on Earth is 9.8 m/s2 (or 32 ft/s2). This means

that if one dropped a marble off the top of a 10-story building, it would keep


38

increasing its velocity at the rate of 9.8 m/sec every second. The same

would be true for a bowling ball.

Energy

Energy, from the Greek energos, meaning “active,” is spent when a force

pushes and moves an object. In other words, if you push a baby stroller the

distance of 100 meters, then first you had to exert a force on the baby

stroller, and it had to move a certain distance. It took energy for you to push

that stroller.

Energy is measured in units of “Joule” because a man named Professor

James Joule, a 19th century British scientist who studied energy. Energy

comes in many forms: heat, light, electricity, mechanical, acoustical, and so

forth. A Joule is a unit of force x distance. In a formula, that would be:

E = F x d

Example If I exerted 1.0 N of force on an object, and if I were able to move that

object a distance of 1.0 meter, then the energy that I used would be (1.0 N)

x (1.0 m) = 1.0 Newton-meter, which is defined as a Joule.

There are many ways to express energy, and there are many forms of

energy. There’s gravitational energy, potential energy, kinetic energy,

thermal energy, electrical energy, acoustical energy, light energy,

mechanical energy, nuclear energy, and so forth.


39

Their units are all measured in Joules, but occasionally one hears of other

units of energy, such as ergs, electron volts, calories, and so forth.

Potential energy (PE) is energy that is stored and available to use in

some way, such as the electrical energy stored in a battery. Gravitational

potential energy (GPE) is nothing more than the energy’s potential at a

certain altitude, i.e., gravitational energy equals the mass times the

acceleration (due to gravity) times the distance that an object can fall, or

GPE = mgh, where m = mass, g = m/s2, and h = the distance that the object can fall.

This is why waterfalls are excellent sources of gravitational potential

energy. Such natural phenomena are harnessed to change the

gravitational potential energy into hydroelectric power (“hydro” means

water).

Kinetic energy (KE) is the energy of an object as it is traveling at a

certain velocity. The word “kinetic” comes from the Greek word kinetikos,

which means, “to move.” The formula to determine how much kinetic

energy an object has is: KE = ½ m v2 This means that an object of mass, m, has a kinetic energy, KE, equal to ½

its mass, multiplied by the velocity, v, squared (or v x v = v2). Remember to

square the object’s velocity before multiplying it by half of the object’s

mass.


40

Light energy (also known as electromagnetic radiation, or EMR) is the

energy stored in a particle of light (or a wave of light).

In brief, the amount of light energy is equal to a constant multiplied by the

frequency of the light itself, or

E = h v,

where “h” is called “Planck’s constant,” for the German scientist Max

Planck. The symbol, “v,” is the Greek letter for “n,” and is called “nu.” This

sounds just like the word “new.” This symbol stands for something called

“frequency.” One of the laws that we will learn is that the speed of light,

symbolized by the letter, “c,” is not only a constant, with a value of about

300,000 km/s. It also is equal to the wavelength of the light, λ (the small-

case Greek letter lambda), multiplied by the frequency of the light, v. In

other words,

λ x v = c You will learn more about these terms later; just be aware of them for now.

There is also a type of energy called “nuclear energy” or NE. There are

several forms of this, but it is similar to the gravitational energy of a planet

orbiting the Sun, or a moon orbiting a planet. This energy deals with both a

relatively weak force and a strong force. Inside a cell’s nucleus, there is

tremendous energy that keeps the nuclear particles “stuck” together. This is

a very powerful force. If one releases this energy too quickly, it becomes an

atomic, or nuclear, bomb.

Finally, another form of energy is “work.” Essentially, if you do work on

something, then you are using energy. Thus, Force times distance = work,

and the units are expressed in Joules. However, if the object did not move


41

(distance = 0), then Work = F • d = F • 0 = 0. NO WORK, no matter

how much force was applied.

Power

Finally, we have mentioned “power” a few times. The word, “power” comes

from a Latin word posse, which means, “to be able to.” This word later

evolved into the French word, “pouvoir,” which also means, “to be able to.”

Eventually this became the word “power” in English.

Power is equal to the amount of energy that one uses in each unit of time,

i.e., Joules per second. In fact, the unit of power is the Watt, named after

yet another scientist, a Scot named James Watt (1736 – 1819). In any

event, if you can spend a lot of energy (or do a lot of work) in a short

period, then you are very powerful. The formula is: P = E/t

where P is power, E is energy, and t is time.

Examples Imagine that you had to dig a hole eight feet long, six feet deep, and three

feet wide. It would take a lot of “work” for you to do this; you’d use a lot of

energy.

Now imagine that a much stronger and more energetic woman could dig an

identical hole in just 10 seconds. Amazing, huh? While a fictional character

like Superwoman could do it, a real person could not. Even so,

Superwoman is called “super” for a reason.


42

Both you and Superwoman would do the exactly same amount of work,

and use the exact same amount of energy. However, since Superwoman

could do it much faster, it would mean that she was more powerful. Time

means power.

Key Terms and Concepts Momentum force

units of momentum energy

Newton’s Three Laws of Motion work

The Law of Gravity power

Problems 1. What is the momentum of a 2000-pound car traveling at 30 miles per

hour? Give the answer in metric units (change pounds to kilograms;

miles per hour to meters per second).

a) 60,000 kg/mph c) 12,090 kg . m/s

b) 66.7 kg/mph d) 80,400 kg . m/s

2. How much force does a baseball pitcher have to exert on a 250g

baseball to make it accelerate to a speed of 50 m/s the instant that it

leaves his hand?

a) 12.5 Newtons c) 12,500 N

b) 25,000 N toward the batter d) 12.5 N toward the batter

3. How much energy is spent (how much work is done) if that same

baseball travels a distance of 30 meters?

a) 375 J b) 12.5 N c) 12,090 N d) 30 W


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4. According to Newton's Third Law of motion, what kind of action results

for every action?

a) Like b) Reactive c) Reaction d) Forward

5. The total amount of energy produced by a force of 12 Newtons over a

distance of 3 meters is the same as a force of 6 Newtons over a

distance of 6 meters.

a) True b) False

6. Which of these does Kinetic Energy not depend on?

a) Mass b) Speed c) Distance d) Velocity

7. If the time it takes for work to be done is reduced, which of these has to

be used?

a) Energy b) Power c) Force d) Mass

8. Gravitational Potential Energy is not dependant on which of these?

a) The mass of the object

b) Acceleration due to gravity

c) The velocity of the object

d) The height of the object

9. Which of the following is the energy of Electromagnetic Radiation

dependant on?

a) Time b) Frequency c) Mass d) Direction

10. The basic unit of work is the _________.

a) Joule b) Watt c) Coulomb d) dyne


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Answers 1. Divide 2000 pounds by 2.2 pounds per kilogram = 909.1 kilograms.

Multiply 30 miles by 1.6 kilometers per mile = 48 kilometers. Now we

have a 909-kg car traveling at 48 km/hour. But we must change it to

meters per second. 48 km = 48,000 meters and 1 hour = 3600

seconds, so divide 48,000 by 3,600 = 13.3 m/sec. So the momentum,

p = m x v = 909 x 13.3 kg . m/sec = 12,090 kg . m/sec (approx).

Choice c

2. Acceleration is change in velocity per second

From 0 m/s (toward the batter) to 50 m/s (toward the batter) in one

second

Equals 50 (m/s)/s or 50 m/s2 (toward the batter).

Since F = m x a, then F = (0.250 kg) x (50 m/s2) =

12.5 kg-m/s2 = 12.5 Newtons toward the batter. Choice d

3. Since Energy = Work = F x distance =

(12.5) x (30) = 375 Newton-Meters = 375 Joules Choice a 4. c opposite

5. a true

6. c distance KE = ½ m v2

7. b power Power = work / time

8. c the velocity is not part of GPE = mgh

9. b frequency E = h v,

10. a joule


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The momentum (in kg-m/sec) of a 910=kg car traveling north at 13.3

meters per second is 12,100. (910 kg X 13.3 m = 12,100 kg-m/sec)

The kinetic energy of a 25-gram bullet traveling at 500 m/s is 3.125

KJ

The momentum of a 2000 pound car traveling at 30 miles per hour is

12,120 kg-m/sec

If you hold a coin between your fingers in the air, the gravitational

potential energy of that coin is greater if the coin is heavier

Newton’s Laws of Motion do not include objects

Every second that any solid object falls towards Earth, its speed

increases by another 9.8 m/s. After10 seconds of “free fall” all objects

falling are traveling at the same rate of speed.


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47

LESSON 4 - HEAT AND WAVES

The term “therm” comes from a Greek word for heat. Dynamics is a word

that means the actions that are going on. Thus, “thermodynamics” is the

study of what’s going on with objects that are subjected to a form of energy

called “heat.” A device that measures temperature is a thermometer, which

means, “heat measuring device.”

The thermometer was invented by Galileo, and later

improved by Edmond Halley.

Energy comes in quite a few varieties, and heat is one of

them. One can generate heat in many ways. The most

obvious is by burning, which usually produces a fire and usually smoke.

There are two types of burning: chemical and nuclear. Chemical burning

occurs when an element (atom) or compound (molecule) combines with

oxygen and forms the products of carbon dioxide (CO2) and water (H2O),

as discussed below.

Example The “formula” for chemical burning, as noted, could be as follows:

2C8H18 + 25O2 = 16CO2 + 18H2O + ENERGY (heat)

The first group (C8H18) is the chemical formula for gasoline, the fuel that

we put in our cars. The second group (O2) is the oxygen molecule. When

your car engine burns gasoline, the stuff that comes out of the exhaust pipe

(muffler) is the third group (CO2), or carbon dioxide, and the last group is


48

(H2O), or water vapor. The numbers in front of the groups (2, 25, 16, 18)

are the ratios of the molecules in the mixture.

This will be covered later in our lesson on Chemistry. Notice that one of the

end products is ENERGY, in the form of heat. You may have noticed that

your car engine gets hot after running a while.

This type of reaction is a “one way” street. We can’t take water and carbon

dioxide, heat them up, and create gasoline and free oxygen. The Laws of

Thermodynamics will not allow this burning to be a reversible process.

Interesting Background on

Hydrocarbon Fuels

Ideally, it would be wonderful

if gasoline (which is one of

many types of hydrocarbons)

burns efficiently, that 100% of

it becomes water and carbon

dioxide. Unfortunately, we have never been able to make an engine that is

100% efficient. So, in reality, other particles come out of our cars’ tail

pipes, including deadly carbon monoxide (CO).

Hydrocarbon fuels that combine with oxygen to give off heat include:

methane (CH4), acetylene (C2H2), propane (C3H8), butane (C4H10), gasoline

(C8H18), turpentine (C10H16), kerosenes (C12H26 to C15H32), and paraffin

(C30H62). Methane is also known as “natural gas” and is used as a fuel for


49

gas ranges and ovens in many home kitchens. Acetylene is a gas that

burns very hot, and is used in welder’s torches. Propane is a gas that many

campers and outdoor enthusiasts use to fuel their barbecue grills.

Butane is a liquid under pressure, but a gas at room temperature. Butane

burns well, and is the main component in cigar and cigarette lighters.

Gasoline is a liquid, of course. Turpentine is a liquid that we use to thin, or

remove, paint. Kerosenes are liquids, and more of a type of “fuel oil” than a

gasoline – although, thinner than fuel oil. Oil lamps burn kerosene. Some

homeowners choose to heat their homes with “fuel oil”. Wax candles are

mostly paraffin.

Many of the hydrocarbons burn very fast – explosively – like methane,

propane, and gasoline. However, the heavier hydrocarbons burn much

more slowly, like the paraffin in wax candles.

Do not confuse “hydrocarbons” with “carbohydrates”. They sound similar,

and their chemical formulas are similar, but while cars can “eat”

hydrocarbons, humans cannot. Even so, humans can eat carbohydrates

(like potatoes, etc.), but cars cannot.

Do not confuse “gasoline” with “gas”. A gas is any substance that expands

to completely fill its container (like body odor, oxygen gas, water vapor), not

gasoline!


50

Measuring Heat

The tool we humans devised to measure heat is

called a “thermometer.” And in order to measure

heat on a thermometer, we need numbers on it.

Most Americans use the Fahrenheit scale to

measure temperature. A German scientist

named Gabriel Fahrenheit developed this in the

1700’s. He developed this scale to go along with

his new invention, the mercury thermometer.

Earlier liquid thermometers used colored alcohol,

but Fahrenheit used the liquid metal mercury.

Anyway, the Fahrenheit scale is somewhat

awkward, so we will start with it.

There are some important “numbers” in Fahrenheit (F) degrees. For

example, 68o F is “room temperature,” although many people feel that is

still cool. We often hear that certain temperatures are “freezing,” when in

reality 32o F is the temperature needed for water to freeze (turn from liquid

to solid). The boiling point of water is 212o F. Normal body temperature is

98.6o F. While we have become familiar with these numbers, they aren’t

“round” numbers, nor are they based upon science. For example, what

significance is 100o F? Or even 0o F? Nothing.

Scientists use two other scales: the Celsius and Kelvin. A Swedish

astronomer named Anders Celsius who lived in the 1700’s invented the

Celsius scale.


51

The Kelvin scale was developed by a British scientist (originally from

Ireland) named Lord William Thomson Kelvin, who lived in the late 1800’s.

Another name for the Celsius scale is the Centigrade scale. This is

because there are 100 equal degrees between the freezing point of water

(at zero Celsius) and the boiling point of water (at 100 Celsius). The word

“centigrade” means “one hundredth of a degree,” just like 100 cents equals

one dollar. Most of the rest of the world uses Centigrade (or Celsius) for

weather applications.

Of course, there are conversion factors from one scale to another. For

example, to change Fahrenheit temperatures into Centigrade, use the

formula below: oC = 5 (o F – 32o)

9 Example If the outside air temperature were 75 oF, we can change that to Centigrade

like this:

oC = 5 (75o – 32o) = 5(43o) = (0.556)(43o) = 24o C (rounded) 9 9

There are some nice things about using the Centigrade scale. Since “centi-

“ means “hundredth”, like one cent is one-hundredth of a dollar, it is easier

to remember. Room temperature is 20o C; body temperature is 37o C.

These numbers are more rounded than the old Fahrenheit system that

most Americans have grown up with.

On the other hand, if we want to measure exact energy, the Centigrade

won’t work. Why? Because we need a scale in which zero degrees is


52

exactly that – absolutely zero, where there is nothing colder anywhere in

the Universe. Scientists needed a scale that would connect energy and

temperature. And that scale is the Kelvin scale. For example, 0 K is

absolute zero. We regularly use “below zero” numbers in Fahrenheit and

in Celsius However, there are NO degrees below absolute zero. And at 0

K, there is NO energy at all, and the units are Kelvins, not degrees.

Fortunately, the size of the degree in Kelvin is the same as in Celsius; so to

change from one to the other is merely addition or a subtraction.

To change Centigrade to Kelvin, one merely adds 273:

K = oC + 273o

So, at 0o C (the freezing temperature of water), the Kelvin temperature is

273 Kelvins. Sure, that isn’t a round number either, but we really need a

scale whose lowest temperature is zero.

Although scientists did invent thermometers to measure heat, we have

known for more than 100 years that thermometers measure temperature,

not heat. One way to measure how much heat is in hot water is to

measure how long that hot water takes to melt 10 ice cubes. A gallon of

80o C water will melt 10 ice cubes much faster than a quart of 80o C water.

Also, the gallon will melt far more ice cubes in 5 minutes than the quart will.

The gallon of water has more heat than a quart of water at the same

temperature.


53

Heat Transfer

One of the ways energy is transferred is by

moving heat. This is done in three ways:

1. Conduction (touch)

2. Convection (movement)

3. Radiation (heat waves)

When we touch a hot stove or hot radiator, we feel the heat immediately

on our skin. The heat energy in the stove

transfers directly to our body, if only locally,

through our skin. This is called conduction.

When we take a bath, we notice that the

warmer water may be near the faucet area,

so we use our hands to physically move the

warmer water around, in order to make the

entire bath feel about the same temperature.

This physical movement is called

convection. And when we stand in front of a

bonfire, or campfire, or roaring fireplace, we

can feel the heat from the radiation, or heat waves, coming from the fire.

The same is true if we go to the beach on a sunny day. We feel the Sun’s

heat on our skin, although we aren’t actually touching the Sun. This type of

heat transfer is also called radiation.


54

The Sun radiates the planet

Earth all the time. If the Earth

kept all that energy and didn’t

let it escape into space, the

planet would burn up and even

vaporize in 27 hours! Thus,

there must be a balance, or

type of equilibrium, where the

Earth re-radiates much of that

energy back out into space.

Conductors, Insulators, and Heat Capacity

Some objects (e.g. metals) are able to transmit heat energy very well.

These are called conductors. Objects that don’t transfer heat very well

(e.g. plastics, cloth) are called insulators. Stone is in between a conductor

and an insulator. It is sometimes called a semi-conductor.

Example Examples of conductors include most metals. Aluminum foil gets hot fast,

but also cools quickly. Examples of insulators include wood, fiberglass,

and even air. Examples of semi-conductors include ceramic, which is made

of stone. It takes stone a long time to get hot, but when it does, it holds on

to the heat and cools off slowly.

Heat Capacity, also referred to as Specific Heat, is the ability of an

element or compound to absorb and radiate heat energy.

Example


55

Aluminum has a low heat capacity, which means absorbing a small amount

of heat causes a large increase in temperature. Sitting on a metal car on a

hot summer day will convince you that metal gets a lot hotter than grass

with the same amount of sunshine. But that same car in winter would be

extremely cold to sit on. Wood has a high heat capacity – it is far better as

an insulator. Thus, we have log cabins in the woods, to hold any heat

generated inside. While wood can burn, its temperature does not rise very

much on a hot, summer afternoon.

LIGHT AND SOUND

The previous lesson discussed forms of energy. Energy may be

transferred in waves, which can come in packets of light, or packets of

sound, or both.

Let’s first talk about what a

“wave” is. Imagine going to the

beach, and watching the water

come in, and go out. Each

“packet” of water is called a

wave. And perhaps one wave

comes to shore every 10

seconds or so. Each wave has a

high point, or “crest,” and a low point, or “trough.” The distance from the

crest of one wave to the crest of the next wave is called the “wavelength.”

In a typical ocean wave, that could be as much as 30 feet (about 10

meters).


56

The rate at which the waves arrive is called the “frequency.” For example, if

one wave crest arrives at the shore and the next arrives 10 seconds later,

and the next arrives 10 seconds after that, etc., then, every 10 seconds a

wave arrives.

As mentioned above, then, the frequency of the wave is one divided by 10

seconds, or 1/10 per second = one-tenth of a wave per second = 0.1 /

second. This is also called 0.1 cycles per second, or 0.1 Hertz, after a

German scientist, Heinrich Rudolf Hertz, who studied waves in the late 19th

Century.

Research has shown us that the speed of a wave, “s”, is λ x v

where λ stands for the wavelength (using the Greek letter, λ) and v stands

for frequency (using the Greek letter, v).

Examples Let’s say that the distance from

one crest to the next (the

wavelength) is 3.0 meters

(about 10 feet). Then the speed

of the wave is

Speed = wavelength x

frequency = 3.0 meters x 0.1 /

second = 0.3 m/s (about 1 foot

per second).


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One can also consider many other kinds of waves, including “waving your hand” to say “hello” to someone. As you wave at someone, you are moving

your hand back and forth (probably left and right). Each time you do that,

you are completing one cycle.

This takes no more than about 1.0 second in most cases, so the frequency

would be one cycle per second. The length of the wave would be the

distance from the left side, to the right, and back to the left side, around 60

centimeters (about 1 foot each way, or 2 feet total). Thus, one can find the

“speed” of the wave, or how fast you are moving your hand, by using the

above relationship:

s = λ x v = 0.60 meter x 1.0 / second = 0.6 meter per second,

or 60 cm/sec (about 2 feet per second).

Both light and sound come in “wave packets,” and each has a wavelength

and a frequency. Plus, each has a speed and velocity.

The speed of light, using the symbol “c” is equal to about 300,000

kilometers per second (about 186,282 miles per second). This number is a

constant for all colors, all reference frames, and so forth. The different

colors of light all have distinct and different wavelengths with corresponding

frequencies, but all colors of light travel at the same speed.

Please do not confuse radio waves with sound waves. They are quite

different. For instance, radio waves (like light waves) travel through empty

space at 300,000 Km/s. However, sound waves cannot travel through

empty space. They travel through different materials at different speeds.


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Example Red light has a wavelength of about 6400 Ångströms, while blue light is

much shorter, with a wavelength of about 4000 Ångströms. An Ångström is

a unit of length named in honor of a 19th Century Scandinavian scientist

named Anders Jonas Ångström. It takes 10 billion Ångströms to equal 1.0

meter! However, some scientists prefer using a different unit called a

“nanometer”. It takes 1 billion nanometers to equal 1.0 meter, so in that

sense, 1.0 nanometer = 10 Ångströms = 10 Å. So, using nanometers

instead, red would be about 640 nm and blue would be about 400 nm.

Astronomers use Ångströms while physicists (not physicians) use

nanometers.

The formula, s = λ x v can also be used for light waves. However, instead

of a speed that can change (s), we replace it with the constant speed of

light, c:

c = λ x v Since the wavelengths of light are so incredibly small, it only seems to

reason that the frequencies of light are extremely large.

As mentioned earlier, sound comes in wave packets, too. And sound has

frequencies (sometimes called “pitch”) from very high to very low. While the

speed of sound is NOT a constant, it is constant within a volume that has

the same temperature and density throughout. Why? Because sound

waves must travel through a medium, or in other words, sound must travel

through a solid, liquid, or gas. It cannot travel through a vacuum. Most of us

are used to sound traveling through air, a gas. Therefore, air is the chief

medium for sound.


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At the standard temperature and pressure (like room temperature and

regular atmospheric pressure), the speed of sound, in air, is about 342

meters per second (about 1,100 feet per second). Sound travels much

faster in a liquid, like water, and even faster in a solid, like steel.

Example When you see a thunderstorm, first you see the bright bolt of lightning, then

you hear the awesome rumbling of thunder. Since light travels so fast, you

see the bolt of lightning almost instantly. However, you have to wait for the

sound of the thunderbolt to reach your ears, because it travels at only 342

meters per second, not at the 300 million meters per second that light does.

Therefore, if you see lightning, start counting the number of seconds (use a

stopwatch, or count, 1-Mississippi, 2-Mississippi, etc.). When you hear the

thunder from the lightning, multiply the number of seconds you counted by

342 meters (about 1100 feet). If you counted 5 seconds, then it would be

about 1 mile away (about 5500 feet). If this time span becomes shorter,

this storm is moving toward you. One good thing: if you hear the

thunderclap, the lightning bolt that caused it must have missed you,

because it is the lightning that can kill, not the thunder (no matter how loud

or scary).

Physical Science Lab I Title: Speed of Sound

II Purpose and Theory: To study the concept, and speed, of sound.

Theory: in mechanics, the length of the wave (wavelength) multiplied by

the frequency of the wave is equal to the speed of the wave. In this case,


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the wave we are talking about is a sound wave in air. In the form of an

equation, it is:

Speed = λ x ν

where the wavelength is represented by the Greek letter, λ (pronounced

"lambda"), and the frequency is represented by the Greek letter ν

(pronounced "new"). The letter "x" in the formula stands for "multiplied by."

Sound travels the fastest in a solid, then next fastest in a liquid, and finally,

it travels slowest in a gas (air). In the depths of space where there is a

vacuum (no air or gas at all), sound does not travel. Sound waves need a

medium to travel through.

In this experiment, you will hear sounds that will grow louder or softer as

you move towards or away from them. You will also notice the farther away

you get, the more apparent it is that sound travels slower than light.

III Equipment

• 2 participants

• a noisemaking device (could be a voice, but it must be the same noise

and loudness each time)

• stopwatch

• meter or yard stick

IV Procedure

1. Find a relatively quiet street or park.

2. Mark off 100 meters in 10-meter increments or 100 yards in 10-yard

increments.


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3. Designate a “zero” point, and have your assistant stand there with the

noisemaker device.

4. Walk 10 meters or yards away and, at your signal, have your assistant

make a noise.

5. Listen carefully how loud the noise is.

6. Walk to 20 meters or yards and repeat the scenario.

7. Continue every 10 meters or yards until you reach 100 meters or yards.

8. Return to the zero point and have your assistant walk out to 10 meters

or yards.

9. Make the noise at the same time that you make a visible gesture

towards your assistant, so he or she will know that the sound went off. If

you had a starter pistol (gun), the assistant may see a plume of smoke

the instant the gun is fired, but you can be creative.

10. Start the stopwatch the instant you make the noise.

11. Instruct your assistant to raise his hand immediately upon hearing the

noise.

12. As soon as you notice his hand go up, stop the watch.

13. Do this for each 10-meter or yards increment until 100 meters or yards

has been covered.

V Data, Observations, Calculations

A. Make table of data for when you walked further away from the noise.

The first column would be “position,” from 1 to 10. The second column

would be distance, from 10 up to 100. The third column would be

sound level. Use the loudness of the sound to be equal to 1.0 at the

distance of 10. If the sound is only about half as strong at 20 than it

was at 10, put 0.5 for 20. If, however, the sound at 20 were only 1/4th


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as loud, put 0.25. Continue this all the way to the 100. If you cannot

hear any sound at any of the positions, then put zero (0.0).

B. Note if the wind is blowing and in which direction. The ideal situation

would be calm (no wind). If the wind is blowing in your direction as you

are walking away, the sound will travel farther. If the wind is blowing

towards your assistant as you walk away, the sound will not travel far.

C. Make a second table of data for when your assistant walks away,

stops, waits to listen to the noise, and puts up his/her hand. The three

columns will be position, distance, and time (from the stopwatch).

VI Results

Explain the level of success of the lab. Don’t just say “Well, it was

successful because …”. The speed of sound in normal air is about 343

meters per second, or about 1100 feet per second. If you were to see

lightning in the distance during a storm, and then counted the number of

seconds until the thunder reached your ears, you could tell how far away

the lightning bolt struck. If you wait for 5 seconds, that is about 5500 feet,

or just about one mile.

If you have the chance, try repeating the lab in a liquid, i.e., in a swimming

pool. You will notice the sound travels much faster.

VII Error Analysis

1. Personal

2. Random

3. Systematic


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VIII Questions

1. What is the value for wavelength of a sound that has a frequency of

1,000 Hz? (� = 1000 / sec). Use the value for speed of sound in VI

Results. Use metric units only.

2. Does the speed of sound depend on loudness? Why, or why not?

3. Does the speed of sound depend on AIR temperature? Why or why not?

4. What would an orchestra sound like if the higher frequencies traveled

faster (and thus got to the audience earlier) than the lower frequencies?

Key Terms and Concepts

Temperature scales of Fahrenheit, Celsius, Kelvin Chemical burning Heat Transfer: Conduction, Convection, and Radiation Hydrocarbons Heat Capacity: Conductors, Insulators, Semi-Conductors Types of thermometers Conversion Factors for Fahrenheit to Celsius and back Efficiency of burning Velocity as a function of wavelength and frequency Wavelength Speed of light Frequency Speed of sound Speed of sound Ångström Hertz Wave packet Crest Trough


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Problems 1. Convert 80o F into Celsius.

a) 26.7 oC b) 62.2 oC c) 86.4 oC d) 201.6 oC

2. Assuming that you could burn propane 100% efficiently, what would the

end products be?

a) H2O and CO b) O2 and CO2 c) CO and CO2 d) H2O and CO2

3. If you are cold, which method is the fastest way to get warm?

a) Conduction b) Convection c) Radiation d) Clothes

4. Which method does the Sun use to heat the Earth?

a) Conduction b) Convection c) Radiation d) Light

5. Which has a higher heat capacity – copper or Styrofoam?

a) Copper c) Equal

b) Styrofoam d) NO heat capacity

6. What is the difference between hydrocarbons and carbohydrates?

a) Only carbohydrates burn

c) Only hydrocarbons have energy

d) Neither one has energy

d) Only hydrocarbons burn immediately


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7. Who was Heinrich Rudolf Hertz?

a) The first pain doctor

b) Studied sound waves

c) German scientist who studied light waves

d) Scientist who studied heat

8. Who was Anders Ångström?

a) Swedish astronomer

b) Studies temperature

c) Swiss scientist who studied light

d) Founder of Alcoholics Anonymous

9. What is the frequency of a beam of red light whose wavelength is 6000

Ångströms?

a) 0.05 Hz b) 500 Hz c) 50,000 Hz d) 5 x 1014 Hz

10. What is the speed of sound at STP? (standard temperature and

pressure)

a) about 300 m/s c) 186,000 mph

b) about 600 m/s d) 3 x 108 m/s

11. If you see an ocean wave hit the beach every 8 seconds, what is its

frequency?

a) 0.125 Hz b) 8 cps c) 3.8 x 107 Hz d) 1/8

12. How long is a typical radio wave, which has a frequency of 560 kilohertz?

a) 5.36 x 107 m b) 560 m c) 536 m d) 1.8 x 10-4 m


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Answers 1. a 3. a 6. d 8. c 11. a

2. d 4. c 7. c 10. a 12. c

5. Styrofoam has a higher heat capacity than copper since it takes a long

time to warm up and doesn’t accept heat well. Copper heats up and

cools off quickly. Choice B

9. The frequency of a beam of red light whose wavelength, λ = 6000

Ångströms, and the speed of light is a constant, c = 300,000 km/sec,

then the frequency, ν = c/ λ = 300,000 km/sec divided by 6000

Ångströms = 50 (km/ Ångströms) per second. This is not really an

understandable answer, so we need to convert everything to meters

first. So, wavelength, λ = 6000 Angstroms = 600 nm = 6 x 10–7 meter.

The speed of light, c = 300,000 km/sec = 3 x 108 meters/sec. Thus, if ν

= c/ λ = 3 x 108 meters/sec divided by 6 x 10–7 meter = 0.5 x 1015 which

equals 5 x 1014 Hz. Choice d


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Styrofoam has a higher heat capacity than copper, aluminum, plastic,

or paper

Heinrich Rudolf Hertz was German scientist

Anders Angstrom was a Swedish astronomer

80 degrees Fahrenheit is 27 degrees Celsius

Conduction is the fastest method to get warm

To convert Fahrenheit to Celsius (Centigrade), subtract 32 and divide

by 1.8. (Dividing by 1.8 is the same as multiplying by 5/9)

To convert Celsius (Centigrade) to Fahrenheit, multiply by 1.8 and

add 32. (Multiplying by 1.8 is the same as multiplying by 9/5)

The Sun heats the Earth by radiation

Heat capacity is the characteristic of a material to retain and give off

heat

The speed of a wave “s” is the wave length times the frequency

Radio waves travel through empty space at 300,000 Km/s/


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69

LESSON 5 - ELECTROMAGNETIC RADIATION

Electricity and its study has been around forever. In ancient Greek times,

people could rub against some objects, such as amber, and create static

electricity. Thus was born the Greek word elektron, a type of amber.

Example If you take a balloon, blow into it to inflate it, tie it, then rub it against your

hair; it may pick up enough electrons to make it stick to a nearby wall. This

is because the balloon becomes negative and attracts the positive particles

in the wall. If you live in a very humid part of the country, this does not work

very well. The water particles in the humid air also attract the electrons.

However, as you remove dried clothes from electric clothes dryer (definitely

NOT humid air) you may have noticed socks sticking to shirts. When you

peel the sock from the shirt and hold it near your arm, it attracts your hair.

The understanding, and measuring of electricity,

however, didn’t start seriously until the 18th

Century. One of the best-known early scientists to

study it was America’s Benjamin Franklin. His

studies in electricity – static electricity – spanned

the years of approximately 1747 – 1752. During

the late 1770’s and the 1780’s, a French scientist named Charles Augustin

de Coulomb studied electricity and magnetism.


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Essentially, electricity is all about electrons,

those tiny subatomic particles with a

negative charge. When a whole bunch of

electrons are together on a surface but

they are not moving, this is called static

electricity. When electrons move along a

wire, it is called electric current. These terms make sense, since static

means “no change” or “not moving,” while current is like the continued

movement and flow of water in a river.

Example You plug in an electric appliance, such as a radio, television, or lamp, and

then turn it on. Then electrons flow into and out of the device, as water in a

river flows into a lake and then out of the lake into another river.

There are subatomic particles called “protons.” While each of these

subatomic particles is about 1,800 times heavier than each electron, a

proton has a single positive charge. An electron has a single negative

charge. They are equal and opposite. Nature is so amazing!

Coulomb determined that each electron, and each proton, has a distinct

amount of charge. Because he developed the unit of charge, its name is

the “Coulomb.” One Coulomb of charge has all of the charges of about 6.24

x 1018 electrons (negative charge) or 6.24 x 1018 protons (positive charge).


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Example If you wanted to write out the total number of electrons in one Coulomb of

charge, it would be 6,240,000,000,000,000,000 electrons! Therefore, each

electron has a negative charge of about 1.60 x 10-19 Coulomb. Each proton

has a positive charge of about 1.60 x 10-19 Coulomb.

The current in electrical current means how many electrons pass a certain

point in a second of time. This is called the Ampère, and is equal to 1.0

Coulomb per second. This name honors another French scientist, André

Marie Ampère, who studied electricity during the early 1800’s.

Electromagnetic radiation is a ten-syllable word for energy that

always travels through empty space at 300 million meters/second. We call

the visible portion of the energy light.

Example Our eyes can detect seven

distinct colors: red, orange,

yellow, green, blue, indigo, and

violet (ROYGBIV). We call these

7 colors the “visible” spectrum, or

the range of electromagnetic

energy that can be seen by

humans. Each of these colors

also has a range, or spectrum.

Each color blends into the next

color to form the familiar rainbow.


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Most of the Sun’s electromagnetic

energy is in this range. But, the visible

“range” is so small compared to all of

electromagnetic energy. This means

that humans cannot see most of the

electromagnetic energy spectrum, but

only the small range of visible light.

Example The 7 colors of the rainbow (ROYGBIV) range from about 4000 Å to 6400

Å in wavelength (or 400 nm to 640 nm). However, the entire

electromagnetic spectrum has a range tens of thousands of nm greater.

Among the visible colors, red is the “weakest,”. It

has the longest wavelength and the smallest

frequency. The German scientist Max Planck

determined that the energy of a wave packet of

light is equal to a constant multiplied by the

frequency of that light: E = h ν

Where E is the energy in Joules, “h” is a constant that Planck was able to

determine experimentally (and is equal to 6.6 x 10-34 Joules/Hertz

= 4.136 x 10-15 electron Volt seconds), and ν is the frequency in Hertz. In

his honor, we call the constant, “h,” Planck’s constant. So, as far as visible light is concerned, violet is the most energetic.

However, what is below red and what is beyond violet? Those

wavelengths that are longer than red, and thus, have a lower energy, are

called “infrared.” This means “below red.” Stars that are cooler than the

Sun give off infrared (IR). We humans also give off infrared energy (heat).


73

Example Some people have tried to make everyone believe that there are black

people, white people, yellow people, and red

people. While the skin’s reflectivity varies from

person to person, all people give off the same

frequency of infrared waves. Those with fevers

may have a slightly different frequency of infrared,

and dead people are the same temperature as

their environment. People are not “black,”

although there are dark-skinned people. In the

same way, there are no “white” people either,

although albino people are close. In essence, skin

color is an environmental adaptation.

Another example of electromagnetic radiation is microwave radiation, a

type of energy used both for communications and for warming food.

Finally, we reach radio electromagnetic energy. Some forms of radio

energy have wavelengths of more than a kilometer (more than 5/8 mile).

Both television and radio stations use forms of radio energy to transmit

their signals. They do not transmit sound waves.

Example A radio station on the “AM dial” with a frequency of 1200

kHz has a wavelength of 250 m. Another station, on the

“FM dial,” with a frequency of 95 MHz, has a wavelength of

3.15 m. We find this using λ x ν = c = 300,000,000 m/s.


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Wavelengths that are shorter than violet, and have a higher frequency and

higher energy, are called “ultraviolet,” meaning “beyond violet.” The Sun

does give off quite a bit of ultraviolet light. This results in humans getting

sunburned, or some kind of skin cancer. Most stars also give off quite a bit

of ultraviolet light.

Next along the spectrum is the higher

electromagnetic energy called “x-ray.” The

German scientist Wilhelm Roentgen discovered

this energy accidentally in 1895. Medical students

must take at least one course about x-ray

technology, and it’s called “roentgenology.” When

people need to get an x-ray for possible broken bones, ruptured disks, or

decaying teeth, they must “pose” for an x-ray photo. A few stars give off x-

rays – they are usually the brightest, hottest stars, or they may be part of a

star system with a mysterious star called a “black hole.”

Example The next time that you are at your doctor or dentist’s office, ask if you can

see an image of your most recent x-rays.

The most energetic of all electromagnetic energy, and the one with the

shortest wavelengths, is called “gamma ray.” These are most dangerous.

Gamma rays are given off in nuclear explosions, and they also radiate from

the centers of galaxies. Even a short exposure to gamma rays will cause

death in about 41 minutes.


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Astronomers are scientists

that study the stars. One way

that they can study the stars

is by “gathering” their light,

with a “light funnel,” or

telescope, such as at an

observatory. Then they

examine the electromagnetic

energies from those stars. They use special cameras to make permanent

records of the starlight. A biologist may bring in a specimen and examine a

plant or animal up close in a lab. However, astronomers cannot pull a star

in for close observation, nor can they travel to the stars to study them, at

least not yet.

Key Terms and Concepts static electricity gamma rays x-rays

electric current radio waves microwaves

Energy visible spectrum of light

Power electromagnetic radiation

Problems 1. How many electrons are in 1.0 Coulomb of charge?

a) 1 b) 6.02 x 1023 c) 6.24 x 1018 d) 20

2. How much heavier is the proton compared to the electron?

a) 6.02 x 1024 times b) 1800 times c) twice d) equal


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3. What kind of electricity did Benjamin Franklin study? a) static b) household c) battery d) conducting

4. How many colors are in the rainbow?

a) eight b) infinite c) three d) seven

5. How many regions of the electromagnetic spectrum are there outside

the rainbow?

a) one b) three c) six d) infinite

6. Which is the most energetic electromagnetic radiation?

a) gamma b) radio c) UV d) X-ray

7. What kind of charge do electrons have?

a) positive b) neutral c) revolving d) negative

8. What is the basic unit of charge?

a) the Coulomb b) the Watt c) the Ampere d) Visa

9. What is the basic unit of electrical current?

a) Volt b) Ampere c) Watt d) Coulomb

10. What are the longest wavelengths of electromagnetic radiation?

a) infra-red b) ultra-violet c) radio d) X-ray

Answers 1. c 2. b 3. a 4. d 5. c 6. a

7. d 8. a 9. b 10. c


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LESSON 5 THINGS TO REMEMBER One Coulomb of charge has 6.24 x 10 18 electrons, or 6,240,000 trillion

A proton is 1,800 times heavier than an electron

Ben Franklin studied static electricity

Teal is not a color of the rainbow

Gamma rays are the most energetic electromagnetic radiation

There are 6 colors outside the rainbow

5.0 Coulombs of electrons flowing past the middle of a copper wire in

.10 seconds, then the electric current in that wire is 50 amps

A wave of electromagnetic radiation has more energy if it has higher

frequency

In a nuclear explosion, the most dangerous type of energy is gamma

rays

Astronomers cannot bring what they study into the lab


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LESSON 6 - BUILDING BLOCKS and NUCLEAR ENERGY

Scientists in ancient Greece proposed the existence of a “building block

particle” called atomos meaning “indivisible.” Scientists have learned that

atoms are not indivisible but are made of smaller particles such as protons,

electrons, neutrons, and others.

For thousands of years, scientists have accepted the concept of tiny

particles combining in some fashion to create everything. However, only in

the past two hundred years have they understood the design and function

of atoms.

Scientists identified elements, one at a time, as history moved along. Their

exact make-up initially was nothing more than educated guessing. Later, a

variety of experiments and tests confirmed or denied the theories.

Two things make up all atoms, like this

atom of helium: the nucleus, and any

electrons that are, in some way,

traveling around it. The nucleus

essentially contains two types of

particles: protons and neutrons.

Hydrogen is the only element that has

no neutron in the nucleus of any of its

atoms.

The first model of an atom looked like the Sun, with planets orbiting around

it; or a large planet with many moons orbiting around it. In this way, the

Nucleus

Electron 0.05 mr


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nucleus, or core, is like the big heavy object in the middle. The electrons

are the much smaller, lighter objects orbiting around the nucleus.

Anything smaller than the atom is, by definition, sub-atomic; since atoms

are made of electrons, protons, and neutrons, all three are sub-atomic

particles. The word “proton” comes from the Greek word proton, which

means “first one.” The word “neutron” comes from the Greek word,

neutron, which means “neutral one.” There are also some other quite

unusual and even smaller subatomic particles.

The atoms of some elements do not

combine with anything else. We call

these elements the “Noble Gases”.

However, with the exception of the

Noble Gas family, atoms of all

elements combine with one or more

atoms of other elements.

Sometimes an atom of one element

will combine with another atom of

the same element (just like itself), as mentioned next.

Combinations of atoms are called “molecules,” from the Latin word moles

that means “little mass.” Some molecules are simple combinations of two

atoms of the same element, such as hydrogen gas (H2). Other molecules

like that include oxygen gas, O2, nitrogen gas, N2, and so forth. More

complex combinations of atoms include molecules of two or more different

elements. Examples include carbon monoxide, CO; hydrogen chloride,


80

HCl; table salt, NaCl; and even the large molecule of glucose, C6H12O6,

which has six carbons, 12 hydrogens, and 6 oxygens.

Molecules are quite small, and, obviously, atoms are smaller yet.

Subatomic particles are so small that they can’t be seen at all. We can do

experiments to prove that electrons and other subatomic particles exist.

However, we can’t merely shine a light on, say, an electron and ask it to

stay still so we can photograph it. In fact, any light that we could shine on

an electron would give it a huge boost of energy. It would take off like a

shot – close to the speed of light itself! So, we would never really know

where it was.

All the elements that exist in the universe come from only one element –

and that is the most abundant element in all of space: hydrogen. Henry

Cavendish confirmed this first element in 1766. The word is from the Greek

“hydro” and “genes” which means the “forming agent of water.”

The first and lightest element, hydrogen, is the primary building block for all

other elements. In the high temperatures and pressures of the cores of

stars, four atoms of hydrogen joined together (fused) to make one atom of

the next heaviest element, helium, then went on to build other elements. Example All stars are made of hydrogen gas. After a while, much of the hydrogen

gas turns into helium, and then to carbon, and then to iron, and various

other byproducts.


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Here is how it is done:

4 H = He + 2β+ + Energy

where the energy is [(Δm)c2] and where 4 hydrogen nuclei, through several

reactions, create one helium nucleus. This reaction also gives off two very

small, positive particles called “beta” particles. (β+). They are really positive

electrons. The reaction gives off a great deal of energy.

Recall that “Einstein’s Equation” usually is written E = mc2 to show

how much nuclear energy is produced when subatomic particles seem to

disappear in nuclear reactions. Because actually a very little amount of

matter (mass) becomes energy, this equation SHOULD BE written: E = Δmc2. This is actually the chemical formula for the explosion of a

hydrogen bomb. At the center of every star, the equivalent of untold

numbers of hydrogen bombs are going off each second.

However, there is one very interesting event here. The mass of 4 hydrogen

nuclei is greater than the mass of one helium nucleus. And the two beta

particles are the same very low weight as electrons. So, how can we

physically balance this formula if there is some mass that “disappears”? In

reality, it doesn’t disappear. Instead, the missing mass is converted

entirely into energy. The missing mass, or Δm, when multiplied by the

square of the speed of light (c2) gives an answer in the units of Newton-

meters, or Joules. Thus, stars are nuclear furnaces that create heavier

elements. In the Physical Sciences, we use the capital Greek letter Delta

(Δ) to indicate difference or change. So, missing mass is Δ m.


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Example Our Sun is “losing” mass at the rate of about 600 million tons per second.

It has been doing this for 5 billion years with little noticeable effect. And

every second, matter that would weigh 600 million tons is completely

converted into pure energy.

As an example, if we could “convert” 1.0 kilogram of matter (about 2

pounds) into pure energy every second, what power would that create?

Let’s work it out:

E = (Δm)c2

where (Δm) = 1.0 kilogram, and c = 300,000 km/sec = 300 million m/sec.

And this would then be 300 million joules/sec or 300 million watts of power

= 300,000 kilowatts of power. That’s enough power to run a small city for a

week! And, to a good extent, that is what we do when we use nuclear

power plants.

After a while, helium begins to turn into carbon, by this reaction:

3 He = C + Energy

and much later, carbon is fused into iron:

3 C = Fe + Energy

and so forth.

Nuclear bombs began with the first atomic bombs developed at the end of

World War II. After that war, scientists looked for a way to harness this

massive energy for peaceful uses, such as providing electricity to homes

and businesses. However, one can’t make a bomb go off slowly, so they

searched for other elements to use.


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Atomic bombs, such as the hydrogen bomb, are fusion reactions. This

means that they take several smaller elements and make one larger

element, as mentioned earlier:

4 1H1 = 2He4 + 2β+ + E

Four hydrogen nuclei are fused together, in a chain reaction process to

form one heavier helium nucleus.

In trying to design a nuclear energy power plant, one needs to be able to

control the release of energy over a long period of time, rather than all at

once. The way to do this, scientists found, was through nuclear fission.

This reaction is just the opposite of fusion. Instead of fusing smaller

elements into larger ones, fission takes very heavy elements and splits

them into smaller elements. In some cases, fission also releases a great

deal of energy.

Example One popular type of fuel used in fission processes is Uranium, which is

naturally occurring inside Earth. Every atom of Uranium has 92 protons, all

of them in the atom’s nucleus. Like many elements, Uranium has several

“isotopes” (different versions of the element). For example, U-235 is an

atom of Uranium that has 143 neutrons in the nucleus. Another isotope, U-

238, has 3 more neutrons in the nucleus.

U-238 is much more abundant in nature than U-235. However, it is rather

easy to split the U-235 nucleus to get the energy out, and it is very difficult

to split the U-238 nucleus.


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In the fission reaction with U-235, the nucleus is bombarded with a

neutron, and the nucleus splits into two smaller elements, Barium and

Krypton.

It also gives off about 200 Million Electron Volts (200 MeV) that can be

used peacefully to power homes and businesses. As an example, 1.0

kilogram (about 2 pounds) of U-235 can yield 18.7 million kilowatt-hours of

energy.

Example Because the amount of U-235 on Earth is limited, scientists have found a

way to use the much more abundant U-238. In this new reaction, a neutron

is fired at the U-238 nucleus. Since U-238 will not split apart, it actually

absorbs the neutron, making a new isotope of Uranium, called U-239. The

U-239 nucleus is unstable, and will spontaneously change one of the

neutrons into a proton. Then it will give off a “positron” (a positive electron,

called a beta particle), thus changing the element itself from Uranium to

Neptunium. A short time later, a neutron in the nucleus of Neptunium will

change into a proton. It will give off another positron, thus changing it to

another element, Plutonium.

Note that while all isotopes of Uranium have 92 protons in the nucleus,

Neptunium has 93 protons and Plutonium has 94 protons.

Now that we have Plutonium-239, this new end product can be split into

smaller elements and give off energy, just as U-235. This type of multiple

reaction sequence is called a “breeder reaction”. It occurs in a more

advanced type of nuclear power plant called a “breeder reactor.”


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There are safety concerns in all types of nuclear reactors. However,

technology is improving at such a rate that future problems will be almost

non-existent. And the fuel supply for a U-238 to Plutonium breeder reactor

is almost inexhaustible.

Key Terms and Concepts Atoms breeder reactor nucleus

Molecules creation of heavy elements stellar reactions

Protons atomic fission hydrogen fusion

Electrons atomic fusion helium fusion

Neutrons carbon fusion hydrogen fusion

creation of subatomic particles

Problems 1. How many electrons are in a neutral A) hydrogen atom? B) Lead

atom?

A) a) 0 b) 1 c) 2 d) 4

B) a) 0 b) 60 c) 82 d) 125

2. How many neutrons are in a neutral A) hydrogen atom? B) Lead

atom?

A) a) 0 b) 1 c) 2 d) 4

B) a) 0 b) 60 c) 82 d) 125

3. What is the proton-proton reaction to create helium from hydrogen?

a) 4 1H1 = 2He4 + 2 β+ + energy b) 1H1 + 1H1 = 2H2 + energy

c) 1H1 + 1H1 = 2He2 + energy d) 4 1H1 = 2He4 + energy


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4. How are the heavier and more complex elements made?

a) Explosion of an atomic bomb

b) Decomposition of Uranium

c) By heat deep within the Earth

d) One element at a time, by smaller elements joining together

5. What are positrons?

a) positive neutrons c) negative protons

b) positive electrons d) negative electrons

6. How does matter turn into energy, using Einstein’s formula?

a) E = Δmc2 b) E = Δmc c) E = mΔc d) E = m2Δc

7. According to the following equation,

92U235 + 0n1 = 56Ba + 36Kr + energy

a) After being bombarded by a neutron, U-235 nuclei split into Barium

and Krypton nuclei plus energy.

b) When a lot of energy goes into the nucleus of U-235, it breaks apart

into Barium and Krypton nuclei.

c) Nuclei of Barium and Krypton fuse together to make nuclei of Uranium

and much energy.

d) Energy breaks up into Krypton and Barium.

8. How many atoms of hydrogen are needed to create 1 atom of helium?

a) 1 b) 2 c) 3 d) 4


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9. Which Uranium is used to create the breeder reactor?

a) U-235 b) U-236 c) U-237 d) U-238

10. Atoms of different isotopes of the same element ______________.

a) Have different numbers of protons in their nuclei

b) Have the same numbers of neutrons in their nuclei

c) Have the same number of electrons in their nuclei.

d) Have different numbers of neutrons in their nuclei.

Answers 1. A) b B) c 4. d 7. a 10. d

2. A) a B) d 5. b 8. d

3. a 6. a 9. d


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LESSON 6 THINGS TO REMEMBER There is 1 electron in a neutral hydrogen atom

There are 0 neutrons in almost all neutral hydrogen atoms

Positrons are positive electrons

4 atoms of hydrogen are needed to create one atom of helium

U238 is the Uranium needed to create the breeder reactor

Heavier and more complex elements are made one at a time from the

fusion of atoms of hydrogen, helium, and heavier elements

Einstein’s formula says that Energy is equal to the mass of the matter

that is lost times the speed of light squared

Ne does not represent one molecule of a substance

Producing electric power with a nuclear reactor produces several

nuclear fission reactions


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LESSON 7 - CHEMICAL ELEMENTS

There are over 100 elements, from hydrogen to uranium, and beyond.

While hydrogen is the most abundant element in the universe, it is certainly

not available on Earth in very high quantities! In fact, there is a huge

abundance of iron, nitrogen, oxygen, and silicon on Earth, but very little

hydrogen.

Scientists discovered more and more elements. They decided to arrange

these elements into some sort of table. Then they looked for things that the

elements may have in common with each other. Eventually, the Periodic

Table of Elements was created.

The Periodic Table had a number of scientists who

contributed to it. The actual Periodic Table was developed

by a scientist named Johannes Periodic – no, just kidding!

The real scientist was a 19th Century Russian chemist

named Dmitry Mendeleyev. He determined the “Periodic

Law of Elements”. This states, “Elements show a regular pattern of

properties when they are arranged according to atomic weight.” We call

this regular pattern “periodicity.” Mendeleyev developed the first Periodic

Table in 1869, and his second draft came out in 1871. It has been evolving

ever since.


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Source: http://www.wisegorilla.com/images/chemstry/periodic_table_of_elements.jpg, 01/19/2006.

As one can see, the Periodic Table puts the elements in order, from left to

right. The number at the top of each box (the “atomic number”) is the

number of protons in the nucleus of each atom of the element. The very

first element, hydrogen, has only 1 proton. Uranium has 92 protons, so it is

much further down.

The elements in the right-hand column, known as the Noble Gases, have

all of their electrons spaces filled. Isotopes of elements are just different

versions of the atom, having the same number of protons, but differing

numbers of neutrons. The word, “iso” means “equal” or “the same” and

refers to the number of protons in the atom’s nucleus. It is the number of

protons that tells one what element it is, no matter how many electrons or

neutrons the atom may have.


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Example The lightest element, with the lowest number of protons is the gas

hydrogen. It has only one proton in each atom. In its most common and

most stable state, almost all atoms of this element also have one electron

each – but no neutrons. Therefore, the most common isotope of hydrogen

has no neutrons. However, “deuterium” is an isotope of hydrogen with one

neutron in each atom’s nucleus. Another, called “tritium”, has two

neutrons. These are most rare, and when they are not involved in some

nuclear reaction, they quickly decay to the common hydrogen. Water is a

combination of hydrogen and oxygen in the form of H2O. It can be made

with hydrogen in the form or deuterium OR tritium. Nuclear scientists call

this “heavy water”.

The second element, helium, is also quite rare on Earth. However, it is the

second most abundant element in stars, and, in fact, in the whole universe.

Helium has two protons in the nucleus of each atom. In its most common

isotope, it has two neutrons. “Light helium” is another isotope, having only

one neutron in each atom’s nucleus. This sounds strange, as helium is

lighter than air already. You use it to inflate party balloons.

The Periodic Table continues to put into categories each and every

element, including carbon, silicon, oxygen, sodium, copper, silver, gold,

uranium, and many others. There are about 100 “natural” elements, and

many more that scientists created to study the nuclear process. Most of the

elements made by scientists decay quickly (they fall apart into lighter

elements) and don’t have a long life.


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Isotopes and Radioactivity As mentioned, an isotope is a version of an element. There may be two or

more versions, or isotopes, for an element. Typically each element has a

“stable” isotope that doesn’t change over time. But there are other isotopes

of natural elements that break down and decay spontaneously into lighter

elements. In some cases, this may take seconds, or fractions of seconds;

in other cases, it may take billions of years to decay. Isotopes that decay

all by themselves over time are called radioactive.

Example After a period of time has passed which called a radioactive isotope’s “half

life”, there is only half of the original material remaining. Then, after another

half-life has passed, one-half of what was left has now decayed. Thus, after

two half lives, one half of one half (one-fourth) of the original remains.

Some common radioactive elements include Radium, which decays to half

its original amount in just about 1,622 years. Uranium-238 takes about 4.6

billion years before an original amount decays to about half of what it was.

In essence, some elements never decay completely, because too much

time must pass for all of it to be gone.

Isotopes are radioactive not merely because they break down into lighter

elements. It is not unusual for radioactive decay to produce positrons,

neutrons, neutrinos (very small particles similar to neutrons), alpha

particles (these are the nuclei of helium atoms) and other high-energy, fast-

moving particles. Being near such radioactive materials for an extended

period is dangerous. They travel right through the body. They can

seriously damage cells in the body, as x-rays do.


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Example Up until the mid 1960’s, it was popular to buy a wristwatch with a radium

dial. The dial would glow in the dark all the time. Modern watches have

phosphorescent paint that absorbs light, then glow in the dark for a while.

However, radium dials glow all the time. It has nothing to do with outside

light. The people who worked in watch factories were beginning to die of

cancer and other diseases. Therefore, there are no longer any radium dial

watches.

Each element is built from elements with fewer protons in each atom’s

nucleus. This extends all the way back to the main building block.

Hydrogen’s atomic number (1) means 1 proton in the nucleus of each

atom. And the list of all of these elements is the Periodic Table. However,

the Periodic Table provides much more information. For example, you will

find the number of protons, electrons, neutrons, and the chemical formulae

for the isotopes. In many cases, you will see the atomic structure, too. Plus,

you are given the mass of 1.0 mole of the element’s combined isotope

average. This is often called the atomic mass, given in Atomic Mass Units

or AMU.

The unit 1.0 mole is a large number. While the unit “1.0 dozen” is equal to

the number 12, the unit 1.0 mole is equal to the number 6.02 x 1023. That

would be 602 followed by 21 more zeroes! So, for example, 1.0 mole of

hydrogen atoms has a mass of about 1.0 gram. Also 1.0 mole (6.02 x 1023)

of carbon atoms has a mass of about 12.0 grams. Therefore the mass of

EACH carbon atom is 12.0 grams divided by 6.02 x 1023 or 2 x 10 -23

grams. This is 0.00000000000000000000002 grams. These atomic


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masses (1 AMU, 12 AMU) are written near the element’s symbol in the

Periodic Table, which may be found in most full-sized dictionaries.

THE ELEMENT CARBON Carbon is just about the most important element in the universe. The study

of carbon and its association with life is called “organic chemistry,” because

life forms have one, or more, organs.

Oxygen, hydrogen, and other elements are also critical. ALL life on Earth is

the same, and it is because of carbon. In fact, it is most likely that any and

all life forms anywhere in the universe and in the multiverse are carbon-

based!

For whatever reason, carbon is the

only element that can combine with

itself to make very long chains and

complex molecules. For life to exist,

large, complex molecules are

necessary.

Coal, a common source of fuel, is

mostly carbon. But if coal is heated under pressure, given enough time, it

will form diamonds because a diamond is pure crystalline carbon. And who

would want to burn diamonds?

The formation process for natural diamonds is very complex. We know that

coal is made out of what used to be plants. These plants became buried in

Electrons

Nucleus (800 times actual size)


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Earth’s soil – some as long as 290 million years ago. Long, long ago, there

were tropical swamps in parts of Earth that are no longer there. Green

vegetation flourished in these murky areas.

Generations of these plants died and then settled to the bottom of the

swamps that they were in. Over a long period of time, the organic stuff

released their gases of oxygen and hydrogen. The remaining material was

mostly carbon.

In this long process, many layers of mud and sand built up, covering the

rotting plant parts. This squeezed the organic material more and more until

it became solid. Before the decomposing vegetation turned into coal, the

plant material became a dark brown, heavy organic goo known as peat.

Many cultures use peat as a fuel source because it burns when dried.

However, it is low in carbon and high in moisture compared to coal. Thus,

peat is not as good a fuel as coal.

During millions of years, deeper layers over the peat exerted a great deal of

heat and tremendous pressure on the stuff below. This eventually became

coal. Europe (mostly of what used to be the Soviet Union) has about 44%

of the coal reserves on Earth. North America (mostly the United States) has

about 28%.

With continued heat and pressure over time, the coal is compressed into

crystalline carbon, or diamond. Oddly enough, while less than 5% of the

world’s coal is in Africa, most of the diamonds are there. Interestingly, one

day back in 1866, a boy was walking along the Orange River in South


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Africa. He spotted a very pretty stone on the riverbank. It turned out to be a

21-carat diamond, and the rush was on. A similar “rush” occurred in 1989 in

northwestern Canada.

It is also interesting to note that a number of meteorites from space have

had diamonds inside them. However, they are slightly different than Earth

diamonds.

In the Periodic Table, a vertical

column of elements is called a

“family”. Other atoms that are in the

same “family” as carbon include

silicon, germanium, tin, and lead.

However, try as they might,

scientists have never been able to

repeat the chain-building

characteristic of carbon. Silicon can

form up to 7 bonds in a link, but then it falls apart. The 1960’s television

series, “Star Trek,” suggested that silicon life forms could exist. (Rocks and

stone have a lot of silicon in them, in the form of silicate). In one episode,

Dr. “Bones” McCoy was able to “heal” a rock creature by filling its wound

with cement! The remaining members of the carbon family don’t even do

as well as silicon.

We, as humans, are a carbon-based life form, and so are all mammals, and

all plants. In fact, all life forms have the same chemical orientation.


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In chemical terms, we often hear the words compound, mixture, and

aggregate. Defining these terms is quite easy, actually.

A “compound” is a particle that has two or more atoms of different

elements. If one has an amount of some pure compound, such as sugar or

salt, that is also called a “substance.”

“Mixtures” are combinations of two or more

separate compounds. Examples include

wood, milk, concrete, and so forth. By

examining them carefully, one can see the

separate compounds. Milk is made of water,

calcium lactate, and lipids (fats). Concrete

has sand, rock, limestone, and other

ingredients. Chemists call these

“heterogeneous” mixtures.

There are also “homogeneous” mixtures. One or more of the compounds

dissolves into one of the other compounds. Chemists call the compound

that dissolves the “solute.” They call the compound that causes the other

to dissolve the “solvent.” An example would be salt and water. When you

add salt to water, it dissolves, and the mixture becomes salt water. In this

case, the salt is the solute, and water is the solvent. When the solute

dissolves into the solvent, the resulting mixture is called a “solution.”


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Typically, it is called a solution when the particles of the solute are smaller

than 10 Å (or 1.0 nm or 10-9 meters).

Example What about larger particles in an alleged solvent? If the particles are larger

than 1000 Å (100 nm) in diameter, most likely they will “settle out”. They will

fall to the bottom, like chocolate powder in milk or like the ingredients in

Italian salad dressing. In order to use these products, we always have to

“shake well” before use. Particles that are too large to dissolve end up

being suspended in the solvent. Eventually they settle to the bottom, pulled

by gravity (assuming the particles are denser than the solvent), like fine

grains of sand in a glass of water. A mixture of such a solvent and such

larger particles is called a “suspension,” and it’s a type of “aggregate.”

There is also a middle type of mixture that is neither a solution nor a

suspension. When particles are approximately between 10 Å and 1000 Å

(1.0 nm and 100 nm), they don’t really dissolve, but they don’t really settle

out, either. They are sort of permanently suspended, and they are given a

special name, called “colloidal suspensions,” or simply a colloid.

Many of the newer brands of food supplements are sold but as colloidal

suspensions. The body digests them much more easily. As our bodies age,

it becomes more difficult for them to digest vitamins, minerals, herbs, and

other pills. Thus, by grinding up the minerals into very small sizes in which

they are actually in a state of colloidal suspension, the body will more

readily absorb them. Thus, they will do the body more good.


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Example Fill a glass with water, and add sand. Repeat with other small items. See if

they are solutions or suspensions.

Key Terms and Concepts Mole mixture compound

Isotope aggregate solution

Element colloidal suspension solvent

Radioactivity solute the carbon “family”

half life coal and diamonds tritium

deuterium atomic mass unit, or AMU

stories from fiction (StarTrek, StarWars)

heterogeneous and homogeneous

Problems 1. How many atoms are in a mole of Helium gas?

a) 1 b) 2 c) 100 d) 6.02 x 1023

2. What is the AMU of Carbon?

a) 1.0 b) 2.0 c) 12.0 d) 6.02 x 1023

3. Isotopes are atoms of the same element having different numbers of:

a) protons b) neutrons c) electrons d) atomic numbers

4. If you started with 1000 grams of radium, how many grams would be left

after three half-lives?

a) 500 g b) 250 g c) 125 g d) 62.5 g


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5. Who created the Periodic Table?

a) Hertz b) Angstrom c) Franklin d) Mendeleyev

6. Imagine that you want to get married, but cannot afford a diamond ring.

Would it be a good idea to get a ring with coal on it? Why or why not?

a) Yes. It is cheap and you can clean the coal off of it.

b) No. You cannot squeeze the coal to become diamond fast enough.

c) Yes. She will be thankful at her wedding for any ring.

d) Yes. You can burn the coal to warm your cold, cold heart.

7. Diamond is produced naturally in which one of the following sequences?

a) Diamond, rotting plants, peat, coal

b) Peat, rotting plants, coal, diamond

c) Coal, peat, diamond, rotting plants

d) Rotting plants, peat, coal, diamond

8. What was discovered in 1866?

a) Oil leaking out of the ground c) Gold

b) A large diamond in a river bank d) Uranium

9. What is the name of the fictional stone creature in Star Trek?

a) Stony b) Spock c) Horta d) Bones

10. Mining for diamonds in South Africa is one way to get diamonds. What

is another, “other world” way to do it?

a) Visit Neptune tomorrow c) Watch Star Trek

b) Pick up meteorites here d) Crush coal


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11. The desalination of seawater (removing salt from salt water) requires:

a) Fish b) Light c) Ice d) Heat

12. “Shake before using” salad dressing is a(n):

a) Mixture b) Solution c) Compound d) Aggregate

13. Is concrete heterogeneous or homogeneous? Explain.

a) Heterogeneous, because you can see what makes it up.

b) Homogeneous, because you can see what makes it up.

c) Homogeneous, because you cannot see what makes it up.

d) Heterogeneous, because you cannot see what makes it up.

14. What is the most efficient way to ingest minerals?

a) A suppository

b) An injection

c) Chew well.

d) Swallow a colloidal suspension

Answers

1. d 4. c 7. d 10. b 13. a

2. c 5. d 8. b 11. d 14. d

3. b 6. b 9. c 12. a


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There are 6 x 10 23 power atoms in a mole of Helium gas

12 is the AMU of Carbon

An isotope is a version of an element

Starting with 1,000 grams of radium, there would be 125 grams left after

3 half lives.

Mendeleyev created the Periodic Table

Removing salt from seawater is called desalination

Horta is the name of the fictional stone creature in the TV series Star Trek

Concrete is said to be heterogeneous

Before becoming a diamond, coal must become the following first:

rotting plants, peat, coal and then diamond

In a solution, the solute particles are the smallest


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LESSON 8 - CHEMICAL CHANGE In this section, you will learn about how things change chemically. In

essence, there are three kinds of changes: physical, chemical, and nuclear.

An example of a physical change

would be to take a piece of paper

and tear it. Now it is no longer a

large piece of paper. Now there

are two smaller pieces of paper.

But they are still paper. That has

not changed.

Example Another example would be to take liquid

water, and put it in the freezer. After a while,

it will expand and become very hard – it will

turn into a new solid called “ice.” However, it

is still water, but just in a different state. Or

you can take water and put it in a pot on the

stove. Bring it to boil. Eventually, all the

water will be gone! But the water has not

disappeared, nor become something else. It

has become water vapor. It is still water, but

just in a different form.

All of the above deal with physical changes. In Lesson 6, we learned about

nuclear changes. This occurs when we are changing one element into a

completely different element. For example, changing hydrogen into helium,


105

by fusing 4 hydrogen nuclei (4 protons) into a new helium nucleus

(containing 2 protons). There is no longer any hydrogen.

Chemical changes occur when two or more atoms form a third substance

or perhaps several new substances, or when one or more molecules

change to form one or more new molecules.

Example An example of chemical change would be to take the paper that was torn

and light the paper on fire with a match. As the paper burns, it changes

into other substances – water vapor,

carbon dioxide, and other things. After it

is all burned up, it is no longer paper.

There may be some ashes left over, but

ashes are not paper; tearing a piece of

paper won’t change the fact that it is still

paper. But burning paper will destroy

whatever paper there was, and change it into one or more other things. The

burning paper also likely will catch on fire your clothes, paper plates/towels,

carpets, grease, oil.

Example Chemical change is also true with gasoline. It has a chemical formula of

C8H18, and when it is burned, or oxidized, by combining it with oxygen the

equation is:

2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy

You do not end up with gasoline. The new substance(s) cannot behave like

gasoline.


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Example Some reactions are reversible because you can get back what you started

with. It is not possible to combine water and carbon dioxide to create

gasoline and free oxygen. However, water’s formation process can be

reversed to produce hydrogen and oxygen gasses by passing an electric

current through the water:

2 H2O + Energy = 2H2 + O2

This process is called electrolysis. Do not confuse it with hydrox, which is

a brand of cookie similar to Oreos.

In summary, we have chemical change when one or more items change

into other items and some are reversible.

If you have gotten this far, you have already come across a number of

chemical equations. These are different from math or physics formulae.

They deal with the correct amounts, or ratios, of atoms or molecules on

both sides of an equation. On the left side of the equation are the reactants,

those substances that will react together to become something else. On the

right side of the equation are the products, those substances that have

been created during the reaction process. Energy may be on either side of

the equation.

Another way to display it is:

REACTANTS PRODUCTS

The reaction may be “exothermic” (giving off energy in the form of heat), or

“endothermic” (taking in energy, in the form of heat, to make the reaction

work).


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The chemical equations must be balanced. The number of atoms of each

element on the left equals the number of atoms of the same element on the

right. Matter cannot disappear.

Example An example would be the reaction of gasoline with oxygen:

C8H18 + O2 = CO2 + H2O

This equation is not balanced. Why? Well, on the left side there are 8

atoms of carbon. On the right side, there is only one atom of carbon. Also,

there are 18 atoms of hydrogen on the left, but only 2 on the right. There

are 2 atoms of oxygen on the left, and 3 on the right. Since 18 does not

equal 2, and 3 does not equal 2, we must “manipulate” the formula so we

have the same numbers of both on each side. HINT: manipulate any “free

agents” available at the end of your chemical balancing. See that the

oxygen molecule, O2, is not combined with anything else on the left side, so

you would do that one last.

First, we see that 8 carbons are on the left, but only one is on the right, so

let’s multiply the CO2 molecule by 8, and this will then result in:

C8H18 + O2 = 8 CO2 + H2O

Is it balanced now? No. While there are 8 carbons on the left, and 8

carbons on the right, there are still 18 hydrogens on the left, and only 2 on

the right. So, let’s multiply water, H2O, by 9, which will result in:

C8H18 + O2 = 8 CO2 + 9 H2O

This gives us 8 carbons on both sides, and 18 hydrogens on both sides.

But is it balanced? Not yet. Why? There are still 2 oxygens on the left side

of the equation and 25 on the right side. So, to balance the equation, we

need to multiply the oxygen molecule on the left, O2, by 12 ½:


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C8H18 + (12 ½) O2 = 8 CO2 + 9 H2O

Now, is it balanced? Yes, but we usually don’t have fractional molecules or

fractional atoms. So, instead of having the number 12 ½, we choose to

multiply the entire chemical equation by 2:

2 C8H18 + 25 O2 = 16 CO2 + 18 H2O

Now, is everything done? Almost. We need to add the energy output of the

burning of gasoline:

2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy


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Physical Science Lab I Title: Testing Chemical Change II Purpose: To see the way a test kit changes with acids, bases, and neutral

fluids.

III Equipment

• A swimming pool test kit

• Acid (vinegar, or lemon juice)

• Base (colorless ammonia)

• Water

IV Procedure

1. Test each of the fluids listed above and observe, record each color.

V Data and Calculations

VI Results

VII Error

VIII Questions

1. Why do swimming pool service persons use test kits?

2. What would happen if your swimming pool had too much acid? Too

much base?


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Key Terms and Concepts Electrolysis balanced equation endothermic

chemical change nuclear change exothermic

physical change nuclear change product

Reactant

Problems 1. Balance the equation CH4 + O2 = CO2 + H2O

a) 2CH4 + O2 = 2CO2 + H2O

b) 2CH4 + O2 = 2CO2 + H2O + energy

c) CH4 + 2O2 = CO2 + 2H2O

d) CH4+ 2O2 = CO2 + 2H2O + energy

2. Complete, and balance, the equation C3H8 + O2 =

a) C3H8 + 3 O2 = 3 CO2 + H2O

b) C3H8 + 3O2 = 3CO2 + H2O + energy

c) C3H8 + 5 O2 = 3 CO2 + 4 H2O

d) C3H8 + 5O2= 3CO2 + 4H2O+energy

3. In the burning of pure gasoline, what is NOT produced?

a) Heat b) CO2 c) Smog d) H2O

4. Are atoms of one element changed to atoms of any other element during

a chemical reaction?

a) Always b) Never c) Sometimes d) Rarely


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5. What is the balanced chemical equation for electrolysis?

a) 2 H2O + energy = 2 H2 + O2

b) 2 H2O = 2 H2 + O2

c) CH4+ 2O2 = CO2 + 2H2O + energy

d) 2 H2O = 2 H2 + O2 + energy

6. What is the balanced chemical equation for burning gasoline?

a) C8H18 + O2 = CO2 + H2O

b) 2 C8H18 + 25 O2 = 16 CO2 + 18 H2O

c) C8H18 + O2 = CO2 + H2O + Energy

d) 2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy

7. What is the balanced nuclear equation for fusing hydrogen into helium?

a) 1H1 = 2He4 + β+ C) 1H1 = 2He4 + 2β+ + Energy

b) 1H1 = 2He4 + β+ + Energy d) 4 1H1 = 2He4 + 2β+ + Energy

8. Which of the following is NOT one of the states of water?

a) Ice b) Liquid c) Salt water d) Water vapor

9. What does an endothermic reaction do?

a) takes in heat b) gives off heat c) produces water d) doubles energy 10. Which of these form products?

a) materials b) heating c) growth d) reactants

Answers 1. d 3. c 5. a 7. d 9. a

2. d 4. b 6. d 8. c 10. d


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Water is never ionic

In the burning of gasoline, the products are carbon dioxide, water and

energy

When gasoline burns no atoms are changed into other atoms

In chemical change, the products are not the same substance as they

were before the reaction

Getting sawdust from lumber is a physical change

The burning of gasoline is exothermic


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LESSON 9 - OTHER PHYSICAL SCIENCES Astronomy is among the oldest of the sciences. In reality, it is the branch

of physics known as “astrophysics.” Astronomy has two branches: stellar astronomy (stars, galaxies, nebulae), and planetary astronomy (moons,

planets, comets, asteroids).

Planetary Astronomy

Studying the planets and the Moon

can be most interesting. Most of the

mass of the Solar System is the Sun

itself. But the Sun is a star, and will

be discussed later. The topics of

study in planetary astronomy include

planets, moon, comets, meteors, and

asteroids, and other things related to

them.

There are nine major planets. In their order from the Sun; they are

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.

To help you remember that, make up a “mnemonic” (word clue) to assist

you. For example, take the first letter of each of the planets and string them

together, like this:

MVEMJSUNP


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Of course, in and of themselves that won’t help much. But now use those

letters to make new words and thus, a sentence; the sillier, the better. How

about:

Main Valves Explode Making Janitors Stand Under New Pipes You get the idea. There are many such “games” to help you remember.

There are two types of planets: big and small. The big ones are really just

large balls of gas, and they are given the name “Jovian Planets” – for Jove,

another name for Jupiter. The Jovian planets are Jupiter, Saturn, Uranus,

and Neptune.

The little planets are small balls of rock. They are Mercury, Venus, Earth,

and Mars. The planet Pluto may be included in here.

The four inner planets are called the Terrestrial Planets, since they are like

Terra, another name for Earth. Of course, Earth is an ideal place to live.

Venus is too close to the Sun, and therefore, too hot. Mars is too far away

and therefore too cold. Earth is “just right.” Mercury is even closer to the

Sun than Venus is. The Jovian worlds are in the frosty cold of outer space.

Seven of the nine major planets have moons. Mercury and Venus do not

have any moons. Earth has a moon called, “Moon.” Mars has two tiny

moons. Jupiter, Saturn, Uranus, and Neptune all have large numbers of

moons. In fact, those planets are almost like tiny solar systems. Pluto has

one moon that is almost as big as Pluto itself.


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Scattered throughout the solar system are the “leftovers”: the cosmic

invaders of comets, meteors, and asteroids. Comets are mostly dirty

snowballs with very long orbits. Asteroids are "wannabe planets” that never

got large enough, and meteors are just made of space dust.

Comets are usually in our skies every night. They may not be bright

enough to be seen easily. Meteors fall from the sky as the Earth gets near

them. Some people call them “shooting stars.” Asteroids are in various

locations, including a large number of them between Mars and Jupiter.

Our Moon is a lovely sight, of course. It travels around Earth in about a

month and goes through various shapes, or phases. Sometimes the Moon

covers the Sun, and that’s called a Solar Eclipse. Other times the Moon

“hides” behind Earth and grows dark in Earth’s shadow. That’s a Lunar

Eclipse.

Planets, moons, comets, meteors and asteroids form as part of a star’s

formation. They are made out of some of the original material that was

there for the star. However, only 20%

of all stars have “solar systems.”

Stellar Astronomy

Stars are so far away that they look

like small pinpoints of light. They are

not just tiny dots, however. They are

about the size of the Sun, which is our


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star. Our Sun is more than 300,000 times heavier than Earth, and

extremely hot. The “surface” of the Sun is 6,000 Kelvin (about 12,000

degrees Fahrenheit). However, the center of the Sun, and any star, is

millions of degrees, which is hot on any scale.

Stars, just like the Sun, create their energy by nuclear reactions. At the

center of all stars, the gas hydrogen is turned into helium, releasing a

tremendous amount of heat.

Stars begin as an enormously large “blob” of gas and dust. Gravity pulls it

all together, and eventually, it “ignites” into a nuclear-burning, self-

sustaining star. And sometimes the star has planets. More often than not,

two or more stars will form out of the same blob of gas and dust. In fact,

about 60% of the stars are really “multiple” star systems.

Stars are so far away that we don’t tend to measure their distances in miles

or kilometers, but instead, in “light years.” As you have learned, light

travels about 300,000 km/s. Since there are about 31.7 million seconds in

one year, during a year’s time, light travels 9.5 trillion kilometers (5.9 trillion

miles). This distance is called a “light year”.

Stars take about 1 billion years to form. Then they last a long, long time.

Some live 10 billion years or more. Our Sun is 5 billion years old. When

stars get older, they first expand their outer layers and become quite large,

and much cooler. They are then called “Red Giants,” and they are so large,

their outer layers would reach out to Jupiter – or beyond! About 1 million

years after this, the outer layers escape into space, leaving a very small,


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dense, bright star called a “White Dwarf.” The size of a White Dwarf can be

about the same as Earth, but 300,000 times heavier! A few stars shrink

even smaller and become “Black Holes” and disappear.

Some stars form in groups called clusters. These can be relatively small

groups of 100 or fewer, or as many as a few million. However, once a

group of more than a billion stars forms, it is called a galaxy.

Our galaxy is called “the Milky

Way” because the word

“galaxy” comes from the

Greek word galactos, which

means “milky way.” Our

galaxy contains about 400

billion stars, and it also has

two smaller “satellite” galaxies

that go around it, just like a

moon orbits a planet.

In our “galaxy neighborhood” there are at least 20 galaxies. The largest in

the group is called the Andromeda Galaxy. It has slightly more than our

400 billion stars, and it is at a distance of 2 million light years away.

Andromeda also has two satellite galaxies revolving around it.

Galaxies come in different shapes and sizes, too, and they are at different

distances. The “closest” galaxies are less than 2 million light years away,

while the most distant are about 20 billion light years away.


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The most distant objects that we see are believed to be the nuclei of newly

forming galaxies. We call them Quasi-Stellar Radio Sources, or “Quasars”

for short.

Our universe, called “the Universe,” seems to be expanding, or getting

larger. If it were the shape of a ball, its diameter might be 40 billion light

years, or more. There are some mysteries left to solve, such as what

happens to a star once it shrinks down to the size of a pinhead, and then

disappears from time and space? This is the “black hole,” and it occurs

when very heavy stars collapse under the force of gravity until they vanish.

Do they go into another universe, or what? It is thrilling to think about.

Geology is the science of Earth. The word

geo is an ancient word for Earth, and logos

means “the study of.” Thus, geology is the

study of Earth. The science of geology is

really a branch of physics called “geophysics.”

More specifically, geology is the study of what

makes up the solid Earth, essentially from the surface to the core. As a

result, mountains, valleys, hills, craters, volcanoes, glaciers, lava, rocks,

and minerals are all part of geology. Geography is a branch of geology,

specifically dealing with the Earth’s surface. Cartography, which is part of

geography, is the study of map-making.


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Example For great adventurers and explorers, a good map is a must. The famous

discoverer, Christopher Columbus, was not

only a sailor, but also a mapmaker.

The Earth’s Surface On Earth, the GeoChemical Rock Cycle is a cycle that rocks pass through. In this

cycle, volcanoes belch out hot, melted

material (called magma) from deep in the

Earth. As soon as this magma hits the air, it becomes lava. Some of the

lava cools and becomes hard. This is now called an “igneous” rock. Some

of this igneous rock gets washed away, and joins with other rocks. This is

called a “sedimentary” rock, such as limestone. Other rocks combine, and

under pressure, form a dense, heavy rock known as a metamorphic rock,

such as some granites. Then, over a long period of time, a few

metamorphic rocks get heated under pressure, melt, and re-join the hot,

molten material (magma) beneath Earth’s surface again. Thus goes the

cycle.


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Outer Core liquid

Lower Mantle Soft solid

Source: http://yates.nn.k12.va.us/images/rocks.gif, 01/19/2006.

The Inside of the Earth Earth has several spherical layers, or levels, beneath

the surface. The top 50

kilometers (30 miles) or so is

a very thin layer called the

“crust.” Below that is the

“mantle.” The upper mantle

and the crust is where all

earthquakes come from. The

lower mantle is very warm

and quite soft.

Inner Core solid

Crust Solid

Upper Mantle Plastic


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Example The study of Earthquakes is called “seismology.” The Earth’s crust is

divided into sections called “plates.” These plates “float” on the layer below

them – the mantle. These plates are not locked down, and they do move

relative to each other. When the plates move quickly, an earthquake

occurs. Sometimes earthquakes occur between two landmasses, such as

those in California over the past 30 years. Some occur between two parts

of the crust that are on the ocean floor.

The one on December 26, 2004 generated huge waves of water called

“tsunamis”. They caused great death and destruction along coastal areas

in such places as Thailand, Indonesia, Sri Lanka, and nearby areas.

Tsunamis are also sometimes called “tidal waves,” although they have

nothing to do with tides.

The three most active earthquake areas in the world include Turkey, Chile,

and Southern California. However, earthquakes can occur almost

anywhere.

Below the mantle is the outer core, which is liquid nickel-iron. Finally, at the

very core, no matter that it’s 3000 Kelvin or more, the pressure is so high

that it is solid nickel-iron.


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Example In the Jules Verne book, Journey to the Center of the

Earth, a group of explorers is able to “climb down” to the

Earth’s very center. While there, they find a large ocean

of water. That scenario, however, is just fantasy. In

reality, we have a large core of rock-solid nickel-iron. The rotation of the

outer liquid core helps create the Earth’s magnetic field. A magnetic

compass can help you find the directions of north, south, east, and west.

The Earth’s insides are similar to those of other planets, too. For more

information on this, take a course in Earth & Space Science.

Meteorology sounds like the study

of meteors or rocks that fall from

outer space. That is not true. The

word Greek word meteor means

“high in the sky”. Those who study

the weather and the climate are

really studying what is going on in

the sky overhead – the air that is

“high in the sky.” A person who studies the weather is a meteorologist. The

science of meteorology is really the branch of physics called “atmospheric

physics.”

Example Well, then, what do we call a person who studies those rocky meteorites

from outer space? A meteoriticist!


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In studying the Earth’s air, also

known as the Earth’s atmosphere,

scientists realize that the air is

thickest, or heaviest, at the bottom.

The air that is way up in the sky is

thin, such as the air at the top of a

mountain. Anyone who lives near

the ocean, but vacations in the mountains, immediately notices a lack of

oxygen when they go up high, causing them to gasp for breath.

The Earth’s atmosphere has six lower levels. The lowest level of Earth’s

atmosphere, which is about 8 to 11 kilometers up (5 to 7 miles) is called the

“troposphere.” The

Latin word tropo

means “to change” or

“to turn,” and, it has

the same root as the

word “tropic.”

The word “sphere”

means a ball. The

troposphere is where

we live. The air is most

turbulent here.

Above the troposphere is the mesosphere (meso means “middle”), and the

two are separated by a boundary called the “tropopause” (“pause” means

“to stop.”) The lowest level of the mesosphere is often called the


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“stratosphere”. That is where the “jet stream” is located and where

commercial airline jets fly. The word “stratos” comes from the Latin stratus,

meaning, “to spread out.”

Above the mesosphere is the ionosphere (from “ion,” a charged particle),

where the air is extremely thin. However, the few atoms that are in the

ionosphere get turned into ions (they lose electrons) when the strong solar

rays hit them. The boundary between the mesosphere and ionosphere is

called the “mesopause.”

Finally, the most outer part of Earth’s air is the exosphere (exo means

“away” or “out from,”) meaning the most far away sphere of air. It is virtually

a perfect vacuum out there.

Weather changes occur due to the Sun’s heat combined with the Earth’s

rotation. Local conditions, such as mountains and nearness to water, also

affect weather.

Clouds Clouds are an important part of

weather. Most people think clouds

are made of water vapor.

However, water vapor is invisible.

Clouds are made up tiny water

droplets, and they are constantly

changing. You will never see the

same cloud twice, even if you look away for one second.


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You may see different types of clouds twice, but not the exact same cloud.

And different types of clouds exist at different levels.

The Main Types of Clouds Are:

1. High – Cirrus family (Cirrus, Cirrostratus, Cirrocumulus)

2. Middle – Alto family (Altostratus, Altocumulus)

3. Low – Stratus family (Stratus, Stratocumulus, Nimbostratus)

4. Vertical – Cumulus family (Cumulus, Cumulonimbus)

Nimbus is Latin for “cloud.” The vertical clouds often lead to heavy summer

thunderstorms. And sometimes there are very heavy desert

thunderstorms, but the raindrops evaporate before they ever reach the

ground!

Climate Climate (from the Greek klima, meaning the angle of the Sun) is the

average type of weather in a certain location, over a period of many years.

The climate in any one place is the same for many centuries.

Examples Meteorologists classify climatic regions in a number of ways. However, for

this lesson, we shall use only two: by temperature and by precipitation.


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There are five climate zones based upon temperature:

1. Tropical (averages above 20° C or 68° F all year). Examples are the

tropics, such as the Caribbean.

2. Subtropical (averages above 20° C at least 4 months and the rest no

colder than 10° C). Examples include states like Georgia and

Alabama.

3. Temperate (4 - 12 months at 10° - 20° C). States like Missouri and

Illinois.

4. Cold (at least 1 month at 10° - 20° C, and the rest cooler). Canada is

an Example.

5. Polar (averages are below 10° C all year). Central Alaska.

There are eight climate zones based upon precipitation (rain or snow):

1. Equatorial (rain all year). Examples would include the Amazon.

2. Tropical (rainy summers and dry winters). South Florida.

3. Semi-agrid Tropical (dry most of the year, with some summer rain).

Parts of Texas and New Mexico.

4. Arid (dry all year). Las Vegas

5. Dry Mediterranean (dry most of the year, but some winter rain). Los

Angeles

6. Mediterranean (dry summers and rainy winters). Nice, Rome, Athens

7. Temperate (rain all year – but not as much as Equatorial). Missouri.

8. Polar (little rain or snow all year). Pt. Barrow, Alaska; Novosibirsk,

Russia.


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The one city in the United States with the “best” all-around weather is San

Diego, California. It is about 75 oF every day and about 55 oF every night all

year round, with many sunny days and not much rain. Yuma, Arizona, is

the “sunniest” city, with 360 days of sunshine per year. The Southeast is

very warm and very humid in the summer. The Southwest is very hot and

very dry in the summer. The Northern Plains and Northern New England

are bitterly cold in the winter. And there are many other examples. Consult

your local newspaper or news & weather station for daily and yearly

temperatures and precipitation.


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Physical Science Lab

I Title: Weather II Purpose

To study wind, sky, rain, clouds, and other weather-related items.

III Equipment

• Access to a weather reporting source (newspaper, TV, radio, Internet)

• Calendar

• Thermometer

• Barometer (optional) measures atmospheric pressure

• Anemometer (optional) measures wind speed

IV Procedure

1. Check local listings of the highs and lows for the past 5 days. Record

2. Check local listings of the weather conditions for the past 5 days

(cloudy, windy, rainy, sunny, etc.)

3. Observe the weather over the next 5 days (highs, lows, conditions) and

record.

4. Make a prediction of the weather over the next 5 days (without cheating

and looking in the paper). Record.

5. After that 5 days, check the local listings of what the weather really was,

and compare what really happened with what you had predicted.

V Data and Calculations

(The data will be your table of temperatures, etc., vs. dates)

VI Results

Well?

VII Error

If you were not exactly correct, why not?


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VIII Questions

1. Why do they call meteorology an inexact science? Isn’t science exact?

2. How many climate zones are in the United States?

3. Which city has the most moderate, or, even temperature, in the U.S.?

Key Terms and Concepts Planet climatic regions climate

Moon precipitation meteorology

Comet meteoritics Earth’s Magnetic Field

Asteroid Inner and Outer Core Seismology

Meteor Tsunami Mantle

Sun Earthquakes GeoChemical Rock Cycle

Solar System Crust Geograp

Star Cartography Quasar

Red Giant “Geology” Cluster of Stars

White Dwarf Galaxy Black Hole

Igneous, Sedimentary, Metamorphic

troposphere, mesosphere, ionosphere, exosphere and all other

atmospheric levels

clouds and their various types Problems 1. What is the difference between a planet and a star?

a) Planets orbit stars

b) Stars orbit planet.

c) Planets move, stars do not

d) Planets have names, starts do not


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2. What is the difference between a planet and a moon?

a) Moons move, planets do not c) Moons orbit planets

b) Planets have names, moons do not d) Planets orbit moons

3. For each term in Column A, choose the correct definition from Column

B.

Column A Column B

i) Comets a) Shooting stars

ii) Meteors b) Wannabe planets

iii) Asteroids c) Moons

d) Dirty snowballs

4. How many planets are in the Solar System? Which is NOT one of them?

a) 9, Titan b) 8, Venus c) 9, Jupiter d) 8, Mars

5. What is the name of our galaxy?

a) Nestle b) Milky Way c) Andromeda d) Constellation

6. How many stars are in our galaxy?

a) 9 b) 1,000 c) 400 million d) 400 billion

7. What is formed when a star shrinks until it vanishes?

a) Meteor b) Black hole c) Dwarf d) Super nova

8. What is the name of the galaxy-like nucleus at the edge of the universe?

a) Asteroid b) Constellation c) QUASAR d) Andromeda


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9. “Geology” is the study of:

a) Earth b) Gems c) Weather d) Stars

10. ____________ was a mapmaker and famous discoverer.

a) Ben Franklin b) Columbus c) Galileo d) Eric the Red

11. What is a tsunami?

a) A Sushi dish c) A Chinese train station

b) A Japanese car d) A large wall of water

12. What region of the Earth does NOT have great earthquake activity?

a) Chile b) Canada c) S. California d) Turkey

13. What causes the Earth’s magnetic field?

a) Wind from the Sun c) Rotation of outer liquid core.

b) Light from the moon. d) Rotation of the oceans.

14. What is the job title of a person who studies meteorology?

a) Meteorist c) Weather man

b) Meteorology person d) Meteorologist

15. What is the job title of a person who studies meteorites?

a) Geologist b) Meteoriticist c) Star chaser d) Scientist

16. Explain the GeoChemical Rock Cycle


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17. Describe the layers of the Earth’s insides

18. Name the six lowest levels of Earth’s atmosphere

19. Name the 4 main cloud types.

20. Climate can be classified as a function of what two items? List the

subcategories of climate regions for each of these two.

Answers 1. a 5. b 11. d

2. c 6. d 12. b

3. i d 7. b 13. c

ii a 8. c 14. d

iii b 9. a 15. b

4. a 10. b

16. The GeoChemical Rock Cycle is: magma to lava to igneous to

sedimentary to metamorphic to magma.

17. The layers of the Earth’s interior are, from top to bottom: crust, upper

mantle, lower mantle, outer core, inner core.

18. The six lowest levels of Earth’s atmosphere are: troposphere,

tropopause, stratosphere, mesosphere, mesopause, and ionosphere.

19. The 4 main cloud types are high, middle, low, and vertical.


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20. Climate can be classified as a function of temperature or precipitation.

The subcategories regarding temperature and precipitation are as

follows:

temperature precipitation Tropical Tropical

Subtropical Semiarid Tropical

Temperate Arid

Cold Dry Mediterranean

Polar Mediterranean

Temperate

Polar


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Vulcan is not a major planet in our Solar System

The name of our galaxy is the Milky Way

A tsunami is an earthquake-generated tidal wave

There is a high rate of earthquake activity in Chile

Exosphere is not one of the lowest levels of Earth’s atmosphere

Climate is a function of temperature and precipitation

A comet is a snowball in space

An asteroid is a minor planet

The rotation of the Earth’s outer liquid core causes the Earth’s

magnetic field


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END OF COURSE REVIEW

There are 24 time zones around the globe

There are 3600 seconds in an hour

Time is one-dimensional and space is 3-D

A photographic image is two-dimensional

A natural biorhythm is the human heart (at rest) beating about once

per second

Two liters of soda filling a plastic bottle measures that soda’s volume

There are 1,000 grams in a kilogram

Assume that the equator of the Earth is 24,200 miles in

circumference. Now, pretend that you are standing somewhere on

the equator, such as in the country of Ecuador. Now, if the Earth

turns once, completely, in 24 hours, then you be going, in miles per

hour, 1,000 even if you were standing still

Your weight on Earth is greater than your weight on the moon. And

your weight on the moon would be less than your weight on Earth

One pound of solid water is less dense then one pound of liquid water

The momentum (in kg-m/sec) of a 910=kg car traveling north at 133

meters per second is 12,100 (910 kg X 133 m = 12,100 kg-m/sec)

The kinetic energy of a 25-gram bullet traveling at 500 m/s is 3125 KJ

Newton’s Laws of Motion do not include objects in motion coming to

rest

Every second that any solid object falls toward Earth, its speed

increases by another 9.8 m/s. After10 seconds of “free fall” all objects

falling are traveling at the same rate of speed


137

Styrofoam has a higher heat capacity than copper, aluminum, plastic,

or paper

To convert Fahrenheit to Celsius (Centigrade), subtract 32 and divide

by 1.8 (Dividing by 1.8 is the same as multiplying by 5/9)

To convert Celsius (Centigrade) to Fahrenheit, multiply by 1.8 and

add 32 (Multiplying by 1.8 is the same as multiplying by 9/5)

The Sun heats the Earth by radiation

The speed of a wave “s” is the wave length times the frequency

Radio waves travel through empty space at 300,000 Km/s

A proton is 1,800 times heavier than an electron

Teal is not a color of the rainbow

Gamma rays are the most energetic electromagnetic radiation

There are 6 colors outside the rainbow

50 Coulombs of electrons flowing past the middle of a copper wire in

10 seconds, then the electric current in that wire is 50 amps

A wave of electromagnetic radiation has more energy if it has higher

frequency

There is 1 electron in a neutral hydrogen atom

There are 0 neutrons in almost all neutral hydrogen atoms

Positrons are positive electrons

4 atoms of hydrogen are needed to create one atom of helium

Heavier and more complex elements are made one at a time from the

fusion of atoms of hydrogen, helium, and heavier elements

Einstein’s formula says that Energy is equal to the mass of the matter

that is lost times the speed of light squared

Ne does not represent one molecule of a substance


138

Producing electric power with a nuclear reactor produces several

nuclear fission reactions

An isotope is a version of an element

Starting with 1,000 grams of radium, there would be 125 grams left

after 3 half lives

Removing salt from seawater is called desalination

Concrete is said to be heterogeneous

Before becoming a diamond, coal must become the following first:

rotting plants, peat, coal and then diamond

In a solution, the solute particles are the smallest

Water is never ionic

In the burning of gasoline, the products are carbon dioxide, water and

energy

When gasoline burns 0 atoms are changed into other atoms

In chemical change, the products are not the same substance as they

were before the reaction

Vulcan is not a major planet in our Solar System

A tsunami is an earthquake-generated tidal wave

There is a high rate of earthquake activity in Chile

Exosphere is not one of the lowest levels of Earth’s atmosphere

Climate is a function of temperature and precipitation

The rotation of the Earth’s outer liquid core causes the Earth’s

magnetic field


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Documents

By: Dr. David H. Menke v 1 - Continental · PDF fileSurvey of Physical Sciences 7 LESSON 1 -DIRECTION OF TIME AND SPACE Time Clocks, watches, and other devices called “chronometers,”