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Refracting Telescopes
Refracting Telescopes
This kind of telescope also has twoconvex lenses, the objective lens and the eyepiece.
Refracting Telescopes
In refracting telescopes, the objective lensis much bigger, so the focal length is farther,so the telescope is longer too.
Why is it called “refracting”?It refracts here!
It refracts here
What’s the problem?
Refracting telescopes need very large optic lenses. When they get too big it canbe hard to move and also the lens can bendbecause it is too heavy.
Reflecting Telescopes
The light comes in and hits the ___________.The light is ____________ to the ___________and then to the eyepiece.
concave mirror
plane mirrorreflected
Has this ever happened to you?
The best internet is made of optical fibers.
Listen to my story…
The best internet is made of optical fibers.
- The light travels through the cables- Thousands of signals 信号 can go at the same time
So, why is the internet slow?- Many wires we use near here are copper, notoptic fibers. - Copper has more resistance and some of thesignal is lost. - The wires might have many turns that slow thesignal down.
- Some internet websites are blocked (this slows everything down)
- The wires might be old and they “leak” 泄漏 some signal.
Binoculars
Magnifies 会放大
Optical Fibers
A compound light ____________ uses two ___________ lenses.
A microscope ______________ small objects by forming an enlarged image of the object.
microscope
convex
magnifies
A _____________ telescope uses a convex lens to collect, refract, and focus light rays from distant objects and a convex eyepiece to
magnify the image.
refracting
A ____________ telescope uses a concave mirror, a ____________ mirror, and a convex lens to collect and focus light
from distant objects.
reflecting
plane
______________ are actually two refracting telescopes put side by side.
All the light in __________________ have the same wavelength and moves in the same direction.
Binoculars
laser light
Almost no light is lost or absorbed in______________________ which are transparent glass fibers.optical fibers
Refracting Telescopes
Refracting Telescopes
This kind of telescope also has twoconvex lenses, the objective lens and the eyepiece.
Refracting Telescopes
In refracting telescopes, the objective lensis much bigger, so the focal length is farther,so the telescope is longer too.
Why is it called “refracting”?It refracts here!
It refracts here
What’s the problem?
Refracting telescopes need very large optic lenses. When they get too big it canbe hard to move and also the lens can bendbecause it is too heavy.
Reflecting Telescopes
The light comes in and hits the ___________.The light is ____________ to the ___________and then to the eyepiece.
concave mirror
plane mirrorreflected
Has this ever happened to you?
The best internet is made of optical fibers.
Listen to my story…
The best internet is made of optical fibers.
- The light travels through the cables- Thousands of signals 信号 can go at the same time
So, why is the internet slow?- Many wires we use near here are copper, notoptic fibers. - Copper has more resistance and some of thesignal is lost. - The wires might have many turns that slow thesignal down.
- Some internet websites are blocked (this slows everything down)
- The wires might be old and they “leak” 泄漏 some signal.
I think the three most likely reasons your internet is slow are…
The wires are copper, not optical fiber.Copper wires can not send signals as fast as optical fibers.
Also, the wires are very cheap.Some of the wires the workers used are so cheap.There are many people using it at the same time.
China has so many people.
That is probably why your internet is so slow.
What are the qualitative and quantitative properties of 100ml of white milk if its mass is 50g?
Card Prizes!
Remember, you can always save your cards for next year if you are coming back.
Prize 1
Two Candies!!
Prize 2
Four Candies!!
One free HWday next year.
Prize 3
McDonald's Fries (medium)
One no homework day next semester.
Prize 4
McDonald’s SMALL Burger
Prize 5
McDonald’s Burger
And three no HW Days…
Microscopes
eyepiece lens---------------------
objective lens------------------
light source-------------------stage-------------------------
When the picture was clear that means you have the right focal length.
Got it! The right focal length!
When the picture was clear that means you have the right focal length.
Focal length is the distance betweenTwo convex lenses to make an object bigger.
How does it work?
How does it work?
The object is on the stage
How does it work?
The picture goes through the objectivelens and is magnified.
How does it work?
Then the bigger picture goes through The eyepiece lens and is magnified again.
Which brand of gum is the most delicious? BAD TEST!!- There is no way to test it, it is an opinion
Who is the tallest in the class?BAD TEST!!- It is easy to see, there is no test here.
Which brand of gum lasts the longest? (Which brand of gum has the longest life)?GOOD TEST!
- We don’t know the answer and it is somethingwe can test.
The Diaper Test!
Three kinds of mirrors!
Plane Mirror
- A plane mirror is totally flat
- Rays that hit the mirror come backfollowing the law of reflection
- Most mirrors are plane mirrors
Plane Mirror
Concave Mirrors
- A concave mirror curves ( 曲线 ) inwards
- Light rays focus at one place in front of the mirror
- The picture will look upside down ( 倒挂 )
Concave Mirrors
Convex Mirrors
- A convex mirror curves ( 曲线 ) outwards
- Light rays are diverging ( 分歧 ) (they go out to many different places)
- The pictures are smaller and we can see more of them
Convex Mirror
Concave or Convex?
Convex!
Concave or Convex?
Concave!
Concave or Convex?
Concave!
Concave or Convex?
Convex!
Where can we find plane mirrors in daily life? Where can we find concave mirrors in daily life? Where can we find convex mirrors?
Words:
Focussing 调焦magnify 放大
Microscopes
eyepiece lens---------------------
objective lens------------------
light source-------------------stage-------------------------
When the picture was clear that means you have the right focal length.
Got it! The right focal length!
When the picture was clear that means you have the right focal length.
Focal length is the distance betweenTwo convex lenses to make an object bigger.
How does it work?
How does it work?
The object is on the stage
How does it work?
The picture goes through the objectivelens and is magnified.
How does it work?
Then the bigger picture goes through The eyepiece lens and is magnified again.
What are the properties of…
There are two ways to measure physical properties: qualitative and quantitative.
Qualitative properties we can seebut we can’t measure.
Quantitative properties was can see and measure (with numbers)
There are two ways to measure physical properties: qualitative and quantitative.
Qualitative properties we can seebut we can’t measure.
Quantitative properties we can see and measure (with numbers)
What are the qualitative and quantitative properties of…
What are the qualitative and quantitative properties of…
What are the qualitative and quantitative properties of…
Respiratory System
The respiratory systems is a body system. The important parts are the lungs, nose and mouth.The respiratory system takes in oxygen and getsrid of CO2. The respiratory system works with the circulatory system and other body systems to keep you alive.
