Prologue pp1 2012

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Unit 1: PrologueThe Nature of Science

When it comes to looking at life, I always tend to round up, but in Science I know to

simply follow the rounding procedure! P.S. My name is Elle

Do Now: Free Write-Looking back at the murder mystery

case that you cleverly solved… how was your approach as a detective similar to being a scientist?

1.An Observation is:

• is the use of the 5 senses to learn something about the environment.

a. When you observe, you use your ____________ to take in everything that is happening around you, paying close

attention to detail

b. Examples:• The rock is round and smooth.

Senses

Let’s make some observations about our classroom…

• We have only one blackboard in our room.

• What other observations can you make?

2.INFERENCE:

-Are interpretations of your observations.

-In other words, when you infer you form a conclusion based on something you observed.

i. The round and smooth rocks must have been carried here by running water.

b. An example of an inference is:

ii. Since the dog is wagging his tail he must be happy.

iii. Make an inference about something your observe in the classroom.

b. Examples

3. Prediction• Lets looks at this picture again, what

will eventually happen to the circled rock?

How is a prediction different than an inference?

• An educated guess as to what will happen in the near future based usually on your observations and inferences.

• An example of a prediction:i. An angular rock will eventually become

rounded if it stays in the stream. ii. Ms. Gill will wear something stylish

tomorrow.

4. CLASSIFICATION:

• To put things into groups. • We can organize or classify objects

according to some pattern or trend or common characteristics.

5. Measurements

Do Now: What are some measurable properties?

Think on a daily basis, what might be some of the things you measure? Make a list… how do you measure

these variables?

-Mass -Area-Temperature -Volume-Density -Pressure

b. How do we make measurements?

• Our senses are limited by how sensitive or by how accurate they are. To get more detailed information, we use instruments, such as rulers, thermometers, x-rays and telescopes

c. Metric System & Unit Conversion

• The fundamental units of the metric system are:

For Mass______________________ • For Length ______________________• For Liquid Volume ________________

Grams (g)

Meters (m)

milliliters (mL)

Prefix Fun!

• By changing the prefix used with each unit you can change the size of the unit. We will use the following prefixes. (There are others for both larger and smaller units.)

Hecto-(102)

Deca-(101)

Kilo-(103)

Centi-

(10-2)

Milli-(10-3)

Deci-(10-1)

Basic Unit(100)

Prefix Fun!

• You can remember this using the following sentence:

• King Henry died, drinking chocolate milk

Hecto- (102)

Deca- (101)

Kilo- (103)

Centi- (10-2)

Milli- (10-3)

Deci- (10-1)

Basic Unit (100)

• To convert from any unit to any other unit count how many spaces are between them and move the decimal point that far in the same direction.

Let’s look at the meter stick! How many meters (m) are in a meter (m) stick?___

How many centimeters (cm) are in a meter(m)? ___________

1

100

• How many millimeters(mm) are in a centimeter (cm) ?__________ Now if there are 100cm in a meter and 10mm in a cm how many mm are in a m? __________

10

1000

• Decimals are used because they are easier to convert than fractions! In the metric system we use abbreviations! Let’s fill them in below!

Length ___ Mass Liquid Volume meter__________ gram_______ liter________ millimeter_______ milligram______ milliliter______ centimeter_______ ------------ ------------meter __________ gram_________ liter_________ kilometer_______ kilogram______ kiloliter______

m g L

mm mg mLcm

m g L

km kg kL

Please complete the practice questions 1-15

6. Rounding:

• The first step in rounding is figuring out what place to round to and where that place is located. You must remember these place values:

• 2 , 6 4 3 , 9 7 5 , 8 6 4 . 9 3 1

Thou

sand

ths

tent

hsHun

dred

ths

ones

tens

Thou

sand

shu

ndre

ds

Ten

thou

sand

s

Hun

dred

Tho

usan

ds

Ten

Mill

ions

mill

ions

Hun

dred

mill

ions

Billi

ons

Rounding Procedure:

• Step 1: Find the location of place that you are asked to round to. Lets call it: Sparky.

• Step 2: Look at the number to the right of this place lets call it the Boss.

• Step 3: If the boss is a 4 or lower, leave Sparky alone. If the Boss is 5 or higher, round the Sparky up one value.

Rounding Procedure:

• Here is a rhyme to help you remember:

• “Four and below, let it go. Five and above give it a shove”

• For Example: Round 7.289 to the nearest tenth: Answer: 7.3

• Now complete practice problems 1-9!

Do Now:

• Take out HW, add 2pts on point chart if complete

Do Now: In class notes Section, Round the following

to the nearest TENTH!

1) 8.6782) 99.0123) 784.5554) 10.995 )0.3567

= 8.7

= 99.0=784.6

= 11.0

= 0.4

• Also, take out HW, add 2pts on point chart if complete

Check your answers

1. 88 mm = 8.8 cm2. 5.7 km = 5700 m3. 18,500 ml = 18.5 L4. 15,300 g= 15.3 kg5. 0.023 kg= 23,000 mg 6. 0.3 cm = 3.0 mm 7. 5,287,945 mm= 5.287945 km8. 12,300 ml = 12.3 L9. 0.007 km = 7,000 mm10. 0.008 km = 800 cm

Check your answers11) 6.78: 6.812) 8.210:8.213) 3.0682: 3.114) 82.921: 82.915) 15.23: 15.2

16) 75.023: 75.0217) 46.9: 46.9018) 32.97045: 32.9719) 99.9999: 100.00

20) 1.65656565: 1.65721) 100.967: 100.967 (already there)22) 0.011223: 0.011

Check your answers20) 1.65656565: 1.65721) 100.967: 100.967 (already there)22) 0.011223: 0.011

23) List two numbers that would round to 8.7: 8.745 & 8.689

24) Explain why 7.93 rounds down to 7.9:The number to the right of the tenth’s place

is less than 525) Explain why 2.85 rounds up to 2.9:The number to right of the tenth’s place is

greater or equal to 5

  Scientific notation is simply a method for expressing, and

working with, very large or very small numbers.  It is a

short hand method for writing numbers, and an easy

method for calculations. 

7. Scientific Notation

Numbers in scientific notation are made up of three parts: the coefficient, the base and the

exponent.  Observe the example below:

5.67 x 105

  This is the scientific notation for the standard number,

567 000.  Now look at the number again, with

the three parts labeled.

5.67 x 105

coefficient    base   exponent  

In order for a number to be in correct scientific notation, the following conditions must be

true:• 1. The coefficient must be greater

than or equal to 1 and less than 10.2. The base must be 10.3. The exponent must show the number of decimal places that the decimal needs to be moved to change the number to standard notation.  A negative exponent means that the decimal is moved to the left when changing to standard notation

8. MASS:

• Is the amount of matter in an object.

• It is how much “stuff” the object is made of, the number of molecules in it.

How do we measure Mass• Can we count the atoms? One by one? Lol

Nope! Instead we use a triple beam balance which gives us a value usually in grams.

Let’s click here for an interactive triple beam balance!

Is Weight the same as Mass?

Weight is NOT the same as mass, but weight is used to measure the mass of an object on the Earth.Think about what would happen if you weighed your self on the moon. You would weight less because there is less gravity pulling you down onto the scale, even though your mass did not change.

Let’s check our our weight on the MOON!!!

9. Temperature:

• It is the amount of heat energy an object has.

• Typically the faster the molecules vibrate with in a sample of matter the hotter it is.

English Units: Fahrenheit Degrees (F°)

• Water Freezes : 32°F.• Water Boils: 212°F.

Metric Units: Celsius Degrees (°C)

• Water freezes: 0°C.• Water boils: 100° C.

So can you memorize this by tomorrow?!?

No Worries!!!

You have your handy dandy ESRT!

Look at page 13, what is the freezing and boiling temperature for water in Kelvin?

Kelvin Units (K)

• Absolute zero: 0 Kelvin’s• Water freezes: 273 Kelvin’s• Water boils: 373 Kelvin’s

• The lowest possible temperature and occurs when ALL heat is removed.

• It is equal to -272°C.

ABSOLUTE ZERO:

What are three states, or phases of matter?

• Solid (ice) Liquid (water) Gas (water vapor)

10. States of matter:What variable determines the different phases?

Temperature

11. Area:• The amount of space a 2-dimensional object

takes up• For squares and rectangles area is equal to:L xW• L: Length, the longer dimension of an 2 D

object usually measured in meters, centimeters or millimeters.

• W: Width, the shorter dimension of a 2D object.• Note that the units will always end up squared!

Example: 4mm x 2mm = 8mm2

11. Area:Let’s practice using the following steps:• Step 1: Write the formulaExample: Area = L x W

• Step 2: List all the variables including the unknown, WITH UNITS.

Example: L = 4mm W= 2mm A= ?

11. Area:Let’s practice using the following steps:• Step 3: Plug in the numbers,WITHUNITS.

Example: A=4mm x 2mm

• Step 4: Calculate WITH UNITS.Example: A= 8mm2

• Practice the two examples on your own!

Activity!

• Take a ruler and ONE object from the front desk

Try to measure the volume

Do Now

- HW on desk (2pts)- Measurement “Do Now” Worksheet

12. Volume:• The amount of space an

object takes up• For solid cubes and boxes,

Volume is equal to: L x W x H Depending on the size of the object the units may be either cm3 or m3.

12. Volume:• But for liquids, volume is measured

in liters using a beaker or graduated cylinder. There two rules:

1. Always read it at eye level

This is a beaker!

12. Volume:• 2. You must read the meniscus to obtain an

accurate result. Due to cohesion (sticky) properties of fluids, the edges of the fluid touching the glass will slightly rise.

Meniscus = 73 mL

Fluid Displacement:It is easier to measure

irregular shaped objects using fluid displacement. In order to measure this irregularly shaped rock you would drop it in a beaker filled with water and measure the change in volume.

What factors affect Volume?• 1)Temperature• Heating a material will cause it to expand

and take up more space because the molecules need more room to move around. Therefore increasing temperature will increase volume.

• _________________• Cooling a material will result in the

opposite. So decreasing temperature will decrease volume. ____________________

• Think about how your rings fit in the winter… they seem to be bigger!

T V

T V

What factors affect Volume?• 2) Pressure:• Increasing pressure will force

molecules closer together there by decreasing volume. ______________________

• Decreasing pressure will allow molecules to spread out and take up more space thereby increasing volume. _________________

• Let’s model this with a sponge.

P V

P V

This week’s HWMonday: Density HW page 1Tuesday: Density HW pages 2-3Wednesday: Density HW pages 4-5Thursday: Density HW pages 6-7Friday: No HW

Extra Help: Today after school and tomorrow morning

13. DENSITY

• The amount of matter (mass) in a given amount of space (volume).

• It tells us how tightly packed the molecules are, or how close to each other they are.

• If they are packed tightly, the density is high.

DENSITY UNITS

• The unit for measuring density is grams per cubic centimeter, or g/cm³

• Density = Mass Volume M

D V

Step 1

• Write the formula

• Example: Density = Mass/Volume or D=M/V

Step 2

• List all the variables including the

unknown, WITH UNITS.

• Example: D=?M = 38.0gV = 12.0cm3

Step 3

• Plug in the numbers, WITH UNITS.

• Example:D=38.0g/12.0cm3

Step 4

• Calculate WITH UNITS.• Example:

D=3.2g/cm3

ExampleIf an object has a mass of 13.4 grams and a volume 5.7 cm3 what is the density?

Solution:

Let’s Practice !!!

• Please complete the worksheet

Do Now:• Take out homework• Take a review book (in box, on

floor, under do now desk)• Take a marker• Write your name really big along

the length of the book• Also write your name on the inside

cover

14. More on Density

• Each pure substance has its own particular density and it can be used to help identify that material at room temperature.

• For example, liquid water has a density of 1g/cm³ because 1cm³ of water weighs 1 gram. One cm³ of water also occupies 1ml.

• solid quartz has a density of 2.7 g/cm³ Mixtures do not have a precise density.

-Fluids tend to layer based on their density, with less dense fluid on top of more dense fluid. Can you think of any examples?

Let’s check out this video!

• http://www.eram.k12.ny.us/education/components/docmgr/default.php?sectiondetailid=17500&fileitem=4738&catfilter=445

Factors that affect Densitya. Temperature• Cooling a material causes its molecules

to move closer together, making its volume decrease and causing its density to increase.

• Heating a material causes its molecules to move apart making its volume increase and causing the density to decrease

• Note that Mass is staying the same!!!

T VD

TVD

Factors that affect Density:b. Pressure

• Increasing the pressure (squeeze) on a material causes its molecules to get pushed closer together, decreasing the volume, making the density increase.

• Decreasing the pressure causes the opposite effect, since molecules move further apart, it becomes less dense.

• Again, note mass remains the same!

P VD

P VD

So why does density matter?

If a warm gust of wind meets cold air, will the warm air go above or below the cold air?• Since hot air is less dense it will rise!• And Cold air sinks because it is

denser than warm air• This happens when you boil water

This rising and sinking of fluids due to density and

temperature differences is called…

A CONVECTION CURRENT!!!We will touch upon this concept many

times through out the year

15. Density at Different Phases• As a material is heated, it changes

from solid to liquid.

• More heat changes the liquid to gas. The molecules move farther apart, so the volume increases, causing the density to decrease.

• Solids are most dense, gases are least dense

The exception to this rule is water

• As water cools, its volume decreases until it reaches 4° C.

• As it cools from 4° C to 0° C, its volume actually increases, so it becomes less dense again.

• Water is most dense at 4°C, but is still a liquid.

• This is due to my buddy Mr. Hydrogen Bond, you will meet him in Chemistry

• Water at 0°C is solid ice, but is less dense than water, so ice floats!!

• Water is the only material whose solid form will float in its liquid form.

• This is why the top of a puddle, or a lake freezes first.

Do NowFocused free write: Why does

ice float? Is the Dad’s explanation correct?

Do Now: Take a look at my awesome Lava Lamp

• Focused Free Write (goes in class-work section) Why are the colors separated? Why do the blobs move rather

than settle? What processes in earth science can we

relate this phenomenon to?

16. Does size affect density of an object?

• You can NEVER change the density of a material by cutting it into pieces.

• Since change both volume and mass, the ratio will remain the same, therefore each small piece will have the same density as the original large one.

17. Let review some crucial relationships!!!

• Temp. Volume Density

• Temp. Volume Density

You must understand and know these by heart!!!

Let review some crucial relationships!!!

You must understand and know these by heart!!!

• Pressure Vol. Density

• Pressure Vol. Density

Do Now

• Take out both labs! Put “Murder Mystery lab” on top of the “Density, Sweet Density Lab”

• Pass up procedure• The rest of the density packet is due

tomorrow

18. Graphing

• Direct Relationship: both variables “move in the same direction” They both increase or both decrease.

Inverse Relationship

• Variables “move in opposite directions”. One variable goes up and the other goes down.

• One variable changes, but the other remains the same.

• As one variable increases, the other increases and then decreases.

19. More on Charts and Graphs:

Equal values

Equal Value

Circle Graph (Pie Graph)

• A=50% B=25% C=12.5% D= ______

B

A

C

D

21. Change:

• When something observed is different from when it was last observed

Frames of reference to study change.

• What has caused the change?• Time and Space.• An example is: The Earth’s moon

changes because we observe it in different locations in the sky and in different phases at different times during a month.

Rate of change

• How fast did the change happen?

• How much a measurable aspect of the environment, called a field, is altered over a given amount of time – years, hours, or seconds.

The steeper the slope the faster the rate of change!

If the slope is constant, the rate of change is also constant

If the slope is exponential or curved, then the rate of change is not constant!

A flat horizontal line, means the that the value is constant over time and not changing at

all

Formula:

• Change in field value(Difference in• Change in timewhatever you• are measuring)

• Formula is on p. 1 in ESRT

Cyclic Change:

• Changes that repeat over and over in a known period of time.

• Examples are: seasons, sun motions, moon and tides

Cyclic: repeats at known intervals.

• Most changes are cyclic and they are very good to use when we are trying to make predictions

Non-cyclic Changes:

• Changes that do not repeat at all or do not repeat in a known period of time.

• Some examples of these are:

• Earthquakes and Hurricanes.

Do Now• Take out Density packet• Take our Density of Gum Lab! Pass up procedure!• Do now is on the “Do Now Desk”

Do Now: Copy HW for the Week

-Take an Answer Key and practice problems from the “Do Now” Desk

-Check your answers to the LAB

Do Now: Draw this in your class work section

Beaker filled with water: Density = 1.0 g/cm3

D= 1.0 g/cm3

D= 0.8g/cm3

D= 0.2 g/cm3

D= 0.5 g/cm3

D= 3.0 g/cm3

D= 1.5 g/cm3

21. Interfaces

• Changes cannot take place unless there is a flow of energy from one location, which loses its energy, to another location, which gains the energy.

• The energy flows across a boundary where the two materials or systems meet.

• This boundary is known as the INTERFACE

Sharp Interfaces

• These interfaces are very easy to locate.

• An example of an sharp interface is the line where a wall meets the floor.

DIFFUSE INTERFACE

• Some interfaces are not easy to see.

• An example is the boundary between the Atlantic Ocean and the Pacific Ocean.

22. Dynamic Equilibrium

• Sometimes many changes take place, but often they “even” out. It is like your science test grades: some high, some low, but they even out.

• This is called DYNAMIC EQUILIBRIUM

• Our natural environment is normally in a state of dynamic equilibrium, but this balance can be upset. It is easy to temporarily upset this balance, especially on a small, local scale as can happen just in the town of Long Beach.

• Unfortunately, human activities tend to cause permanent disruptions, especially when we pollute.

POLLUTION:

• When the amount of ANY substance, found ANYWHERE, becomes high enough to affect people, their properties, or plant or animal life.

population

pollution

How to make a graph!

It's probably better to do a graph in pencil first, then in pen.

How to make a graph!

• 1. Collect your data. After you have it all in one place, you should have one independent variable (like time) and one dependent variable (like something you measure as a function of time).

Making a Graph

• Here are some points we will use as an example; we've measured position of a ball as a function of time:

time (s) position (cm) 1 3.0 2 3.4 3 4.8 4 5.0 5 5.3

Making a Graph

2. Determine the range of your data. In order to determine how big a graph to make, we need to determine how much the numbers vary. In this case, time varies from 1 to 5 seconds, and position varies from 3.0 to 5.3 cm. We have to make sure that there is enough space on the graph to fit all the data

Making a Graph

3. The independent variable (time, in this case) will go on the x-axis (the one parallel to the bottom of the page), and the dependent variable (position, in this case) will go on the y-axis (parallel to the left hand side of the page). So, draw axes that are big enough for all the data.

Making a Graph

4. Give your graph a Title. Titles of graphs are usually "Y versus X"; so in this case, our title is "Position versus Time." (NOT position divided by time, or position minus time.)

Making a Graph

5. Label your graph and your axes. THIS IS VERY IMPORTANT! When presented with your graph, other people should be able to figure out what is plotted without asking you.

Making a Graph

6. Labels on the axes must have units! So, in this case, the label on the x axis (the one on the bottom) should be "Time (seconds)" and the label on the y axis (the one on the left) should be "Position (centimeters)."

Making a Graph

7.Remember to write the numbers on the graph, too. The numbers should be evenly and logically spaced - what I mean by this is the following: for our position data here, the y-axis should be marked off in increments like (1,2,3,4,5,6) or (2,4,6,8), NOT (1.3, 2.6, 4.8,...) or anything else weird.

Making a Graph

8. Plot your data. Now, go ahead and place your data points on the graph. Make them big enough to be seen, but not big enough to look like you were eating pizza while making your graph.

Making a Graph

9. Draw a "line of best fit." THIS DOES NOT MEAN CONNECT THE DOTS! Only rarely will a graph need to have the data points connected by a jagged line. Usually, it is best to guess at a (straight) line that goes as near as possible to as many points as possible. (See example.) THE ORIGIN IS NOT ALWAYS INCLUDED AS A POINT! And, sometimes there will be a LOT of scatter and it might not be clear where a line should go. Now you're done with your graph, but you're not finished yet.

Making a Graph

10. Think about what your graph means. What type of relationship do the variables have?

20. PERCENT DEVIATION

• This tells us how much error is in some measurements when it is compared to the true measurement. We find the amount of error using the formula:

Difference between accepted and measured value

_________________________ X 100Accepted value

This formula is on the front page of the ESRT.

Example:

• A student determines a room to be 17 ft long, but the blue print for the room is 15 ft long. Find the % Deviation.

• 17-15ft /15 ft X 100% =

Example:

• A student weighs himself on his bathroom scales at home where he is 125 lbs. At the Dr.’s office he actually weighs 135 lbs. What is the % D. of the bathroom scales?

• 135-125lbs / 135 lbs X 100 =

Example:

• •A student calculates that the density of galena is 7.0 g/cm3. Use the back of your reference table to calculate the % deviation.

7.6-7.0 g/cm3 / 7.6 g/cm3 X 100 =

Do Now

• Take Answer Sheet from Do Now desk

Start checking your answers

Corrections

Prologue Review # 12 : 65.93 cm^3#19: 101.0#20: 13.45m and 13450 mm

Measuring Accuracy Answers1. 22. 13. 44. 15. 36. 47. 38. Cant do9. 210. 111. 212. 113. 214. 215. 3

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