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Physics of Light Review Sheet
© Supercharged Science Page 1
Great job on our Physics of Light sessions this month! We’ve covered A LOT in a short amount
of time, so I wanted to be sure you had a chance to really be impressed with the amount you’ve
learned and how much understand about the world of physics!
Here’s what you can do now. First, I’ve put together a vocabulary list for you to review. If you’d
like to, write each of these on an index card (make your own from sheets of paper). Don’t worry
about the definitions just yet.
Next, let’s do a Spelling Bee! Grab a parent or sibling and ask them to test you on how to spell
each one. If there are any that are just too hard (or too easy), remove them from the deck.
If you’re the type of kid that has a lot of energy for movement, then you’ll like this tip: When I
ask kids to spell words, I also have them bounce up and down on beds or trampolines or using a
jump rope to really get them associated with the words.
Ready? Go ahead and work your way through this list.
Vocabulary:
Frequency
Interference
Coherence
Concave lenses
Convex lenses
Radio waves
Microwaves
Infrared
Visible light
Ultraviolet (UV)
X-rays
Gamma rays
Filters
Intensity
LASER
Lenses
Light
Speed of Light
Index of refraction
Photoelectric effect
Polarization
Refraction
Reflection
Scattering
Dispersion
Wavelength
Electromagnetic Spectrum
Physics of Light Review Sheet
© Supercharged Science Page 2
Physics of Light Lab Practical
Now that you’ve got the words down, let’s see how much you really understand about each
one. Instead of writing definitions (that will come later), let’s do a “Lab Practical”. This is how
we’ll really get a sense of how much you understand and if there are any gaps.
Take your stack of words and hand them to someone else. (You can do this by yourself if you
have to, but it’s a lot more fun to do this with a friend, a family member, or even as a “dinner
show” after dinner that you can do for the family.
Now, when this person shows you a card, you have only a minute or two to demonstrate what
that word actually means. In some cases, this will be easy, but in other cases, you may need to
set up a quick experiment or sketch something out. Try to give three separate, different
examples of each one.
The point is to think about how you would demonstrate to someone else about the word on
the card, just like you were the teacher in the room. How would you explain it so they really
understand? Go ahead and do this now for as many of these as you can.
Frequency
Interference
Coherence
Concave lenses
Convex lenses
Radio waves
Microwaves
Infrared
Visible light
Ultraviolet (UV)
X-rays
Gamma rays
Filters
Intensity
LASER
Lenses
Light
Speed of Light
Index of refraction
Photoelectric effect
Polarization
Refraction
Reflection
Scattering
Dispersion
Wavelength
Electromagnetic Spectrum
Physics of Light Review Sheet
© Supercharged Science Page 3
Now it’s time to write actual definitions for each of these. I put together my slides for the
month in this review sheet so you can refer to them if you need to. I am more interested in
making sure you understand a concept and can explain it in to your own words rather than
memorizing a definition I give you, so let’s see how you do before you peek at my slides.
You can write the definitions below in the space provided (drawing pictures is perfectly fine
also), or you can add them to the back of the cards you created back at the beginning.
Primary Colors of Light
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Frequency
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Interference
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Coherence
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_________________________________________________________________________
Physics of Light Review Sheet
© Supercharged Science Page 4
Concave lenses
_________________________________________________________________________
_________________________________________________________________________
Convex lenses
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_________________________________________________________________________
Radio waves
_________________________________________________________________________
_________________________________________________________________________
Microwaves
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_________________________________________________________________________
Infrared
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_________________________________________________________________________
Visible light
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_________________________________________________________________________
Physics of Light Review Sheet
© Supercharged Science Page 5
Ultra Violet (UV)
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_________________________________________________________________________
X-rays
_________________________________________________________________________
_________________________________________________________________________
Gamma rays
_________________________________________________________________________
_________________________________________________________________________
Filters
_________________________________________________________________________
_________________________________________________________________________
Intensity
_________________________________________________________________________
_________________________________________________________________________
LASER
_________________________________________________________________________
_________________________________________________________________________
Physics of Light Review Sheet
© Supercharged Science Page 6
Lenses
_________________________________________________________________________
_________________________________________________________________________
Light
_________________________________________________________________________
_________________________________________________________________________
Speed of Light
_________________________________________________________________________
_________________________________________________________________________
Index of refraction
_________________________________________________________________________
_________________________________________________________________________
Photoelectric effect
_________________________________________________________________________
_________________________________________________________________________
Polarization
_________________________________________________________________________
_________________________________________________________________________
Physics of Light Review Sheet
© Supercharged Science Page 7
Refraction
_________________________________________________________________________
_________________________________________________________________________
Reflection
_________________________________________________________________________
_________________________________________________________________________
Scattering
_________________________________________________________________________
_________________________________________________________________________
Dispersion
_________________________________________________________________________
_________________________________________________________________________
Wavelength
_________________________________________________________________________
_________________________________________________________________________
Electromagnetic Spectrum
_________________________________________________________________________
_________________________________________________________________________
Physics of Light Review Sheet
© Supercharged Science Page 52
Definitions
The three primary colors of light are red, blue, and green. Red and green light mixed together
make yellow light. Prisms un-mix light into its colors (wavelengths).
Concave lenses work to make objects smaller (door peep hole), and are curved inward like a
cave.
Convex lenses make them larger (magnifying lenses), and have a ‘bump’ in the middle you can
feel with your fingers.
Electromagnetic waves are waves that can travel through space. Unlike sound waves (which
require a medium in order to transport their energy), electromagnetic (light) waves are able to
transport energy through the vacuum of space by vibrating electric charge. Electromagnetic
waves have both an electric and magnetic component. The frequencies (wavelengths) these
waves cover is called the electromagnetic spectrum (see next paragraph).
The amount of energy a photon has determines whether it’s a particle or a wave. Photons with
the lowest amounts of energy and longest wavelengths (some are the size of football fields) are
radio waves. The next step up are microwaves, which have more energy than radio waves. IR
has slightly more energy, and visible light (the rainbow you can see with your eyes) has more
energy and shorter wavelengths. Ultraviolet (UV) light has more energy than visible, and x-rays
have even more energy than UV, x-rays are even higher energy and require special protection
when working with this wavelength, and finally the deadly gamma rays have the most amount
of energy.
Filters can be used to block certain wavelengths.
Intensity, or brightness, is the amount of photons (packets of light) you have in a certain
amount of space. A flashlight has less intensity than a car headlight.
LASER stands for Light Amplification by Stimulated Emission of Radiation. Most lasers are
monochromatic (one color). Lasers are concentrated beams of light, and are illuminated by
small particles (like smoke and dust).
Lenses work to bend light in a certain direction (refraction). A lens is a curved piece of glass or
plastic that changes the speed of the light. Lenses have the same effect on lasers as on light
beams.
Physics of Light Review Sheet
© Supercharged Science Page 53
Light is energy that can travel through space. Light can be defined by four things: intensity (how
bright), frequency (or wavelength), polarization (the direction of the electric field), and phase
(time shift).
Objects can either be a light source (like the sun) or reflect light (like the moon).
Light can change speeds, but the maximum light speed is through a vacuum (186,000 miles per
second). Light changes speeds when it passes through a different material (like water, glass, or
fog).
Depending on the optical density of the material, light will bend by different amounts. Glass is
optically denser than water. Water is more optically dense than air.
When two beams of light are out of phase with each other, it’s like playing a G and A on the
piano. This is called phase shift.
Blue and UV light eject electrons from metal plates, but red light does not (photoelectric
effect).
Polarization has to do with the direction of the electric field. Your sunglasses are polarizing
filters, meaning that they only let light of a certain direction in. The direction that the light is
polarized has to do with the electromagnetic field.
When a beam of light hits a window, it bends and changes speed (refraction). Technically, the
wavelength (color) changes but the frequency stays the same. In order for this to happen, the
speed of light must also change.
Razor-edge slits create interference patterns. Slits are skinny holes that allow light to pass
through. Scientists use slits to filter out all other light sources except the one they want to use
in their experiment.
When you change the wavelength, you change the color of the light. The wavelength ()
equals the speed of light (c) divided by the frequency (), or = c / .