Name__________________________________________ Per________________

Waves

I can…

____I can define and describe a mechanical wave

____I can define and describe the properties of mechanicals waves

____I can design an experiment that gathers data about the energy of a wave

____I can compare and contrast light, sound, and seismic waves

____I can identify if a medium is present in a wave system

____I can build a model that demonstrates the interactions of waves and matter

____I can list the colors of the visible spectrum in order according to wavelength

____I can describe how the properties of an object can transform light energy into thermal energy

____I can describe how reflection and absorption of light determine color of an object

____I can define the following terms: transparent, translucent, and opaque

Tracking My Progress

Date Assignment Still

working

Proficient Mastery

Pre-AsseSsmenT

Vocab word 1-no idea 2- I have heard of it, but

don’t know what it

means

3- I have heard of it and

have some idea of what it

means

4- I know this stuff! I

could use it in a

sentence

electromagnetic 1 2 3 4

Spectrum 1 2 3 4

Mechanical wave 1 2 3 4

Compression wave 1 2 3 4

Reflection 1 2 3 4

Refraction 1 2 3 4

Seismic Wave 1 2 3 4

Absorption 1 2 3 4

Medium 1 2 3 4

Wavelength 1 2 3 4

1. Sketch a diagram of what you think a wave of light looks like:

2. Sketch a diagram of what you think a wave of sound looks like:

3. What do you think it looks like when a light wave is refracted? Sketch your idea below:

Types of Waves

Imagine that your family has just returned home from a day at the beach. You had fun, but you are hungry from

playing in the ocean under a hot sun. You put some leftover pizza in the microwave for dinner, and you turn on

the radio. Just then, the phone rings. It’s your friend calling to find out if you’ve done your math homework

yet?

In the events described above, how many different waves were present? Believe it or not, at least five can be

identified! A wave is any disturbance that transmits energy through matter or space. Okay, here are the

answers to the scenario above: water waves in the ocean; microwaves inside the oven; light waves from the

sun; radio waves transmitted by the radio; sound waves from the radio, telephone and voices.

Energy can be carried away from a source by a wave. However, the material through which the waves travel

does not move with the energy. For example, sound waves often travel through the air, but the air does not

travel with the sound. If air were to travel with sound, you would feel a rush of air every time you heard the

phone ring.

As a waves travels, it uses energy to do work on everything in its path. For example, the waves in a pond do

work on the water to make it move up and down. The waves also do work on anything floating on the water’s

surface- for example, boats and ducks bob up and down with the waves.

Key words:

Summary:

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Transverse and Longitudinal Waves

Definitions:

Transverse waves:

Longitudinal waves:

1. Using your knowledge of the waves above complete the table for the type of wave you have been

assigned.

2. Move around the room and meet at least 10 different types of waves and determine whether they

are transverse or longitudinal and fill out the table for each.

Wave name Transverse or longitudinal Explain why:

Sketch a diagram of a longitudinal wave:

Sketch a diagram of a transverse wave:

Slinky Lab

ANSWER ALL QUESTIONS BY EXPLANATION OR DIAGRAM

PROCEDURE 1-

TRANSVERSE WAVES

1. You and your partners stretch a slinky about 4 meters.

2. Place a piece of masking tape in the middle of the slinky so that it is folded and looks like a flag.

3. Practice producing pulses along the slinky by shaking it sideways on the floor or table.

4. Have each partner send single pulses along the spring.

DRAW A DIAGRAM OF WHAT THE PULSE LOOKS LIKE.

WHAT DIRECTION DOES THE PIECE OF MASKING TAPE MOVE AS THE PULSE TRAVELS DOWN

THE SPRING?

WHAT IS THE DIRECTION OF THE PULSE AS THE PULSE TRAVELS DOWN THE SPRING?

WHICH WAY DO YOU VIBRATE A SLINKY TO PRODUCE A TRANSVERSE WAVE?

Procedure 2-

LONGITUDINAL WAVES

1. Grab several coils down on the slinky.

2. Pull and release the coils to produce a longitudinal wave.

3. Have each partner practice sending single longitudinal waves down the slinky.

DRAW A DIAGRAM OF WHAT THE PULSE LOOKS LIKE.

WHAT IS THE DIRECTION OF THE PULSE MOVES AS THE PULSE TRAVELS DOWN THE SPRING?

WHAT DIRECTION DOES THE PIECE OF MASKING TAPE MOVE AS THE PULSE TRAVELS DOWN

THE SPRING?

WHICH WAY DO YOU VIBRATE A SLINKY TO PRODUCE A LONGITUDINAL WAVE?

Procedure 3- SPEED OF A PULSE

PRODUCE TRANSVERSE PULSES & RECORD THE TIME IT TAKES FROM WHEN THEY ARE PRODUCED TO WHEN THEY

TO RETURN TO YOU.

Trial # Type of pulse Time of pulse return (sec)

1 Small pulse

2 Small pulse

3 Large pulse

4 Large pulse

WHAT CONCLUSION CAN YOU MAKE ABOUT THE SPEED OF ANY SIZE PULSE THAT MOVES THROUGH THE SAME

MEDIUM?

Procedure 4- INTERFERENCE OF PULSES

1. Produce a pulse on one side of the slinky.

2. Have a partner produce a pulse on the opposite side of the slinky at the same time.

DRAW A DIAGRAM OF THE PULSES JUST BEFORE THEY MEET

DRAW A DIAGRAM OF THE TWO PULSES WHEN AS THEY MEET EACH OTHER IN THE MIDDLE.

WHAT RULE COULD YOU MAKE WHEN TWO “OPPOSITE-SIDE” PULSES MEET?

Wave Properties

Part 1- Understanding Properties

When a rhythmic disturbance passes through a medium such as a solid, liquid, or gas, a wave is formed. For example,

vibrations that disturb the air create sound waves. An earthquake creates wave disturbances that pass through earth

and solid rock. Water waves are ripples that travel over water, disturbing the water’s calm surface. In each case, a wave

travels through a medium because when one area of the medium is disturbed, it pushes against neighboring areas,

which in turn push their neighboring areas. As the reaction continues, the wave travels away from the place where the

disturbance happens. The speed at which the wave travels through the medium depends on the properties of the

medium.

Waves have three measureable characteristics: amplitude, frequency and wavelength. Write out the definition of each

below:

Amplitude:

Frequency:

Wavelength:

Sketch a diagram of ta wave and label its parts. Include crest, trough amplitude and wavelength.

Part 2- Virtual Lab

Website: http://www.glencoe.com/sites/common_assets/science/virtual_labs/E05/E05.html

Objectives:

Identify characteristics of waves.

Discover the relationship between wavelength and frequency of a wave.

Relate the amplitude of a wave to the magnitude of disturbance of a medium.

Procedure:

1. Select a speed and size for the plunger.

2. Click start plunger and begin to generate waves.

3. Click the step button repeatedly to stop the wave and see each step of its motion.

4. Click the play button to return to normal motion.

5. Using the grid measure the waves’ amplitude and wavelength.

6. Using the timer, measure the frequency of the wave.

7. Record your measurements below.

8. Repeat these steps for different speeds and sizes of waves and record your findings in the bale.

Speed Size Amplitude Wavelength Frequency

Conclusion Questions:

1. How does the size of the ball on the plunger affect the amplitude of the waves?

2. What affect, if any, does increasing the speed of the plunger have on the frequency of the waves?

3. What affect, if any, does increasing the speed of the plunger have on the wavelength of the waves?

4. What is the relationship between frequency and wavelength of a wave?

Calculating Wave Properties

When you measure the properties of a wave you use that information to then determine the value of

additional wave properties.

We can use equations to determine the frequency, wavelength or velocity of a wave.

f = frequency and is measured in hertz (Hz)

v = velocity and is measure in m/s

h = wavelength and is measured in meters (m)

Use the equation v= h x f

Write a sentence that would describe the equation above:

__________________________________________________________________________________________

“I feel the earth move, under my feet….”

For billions of years, Earth has been remodeling itself. Huge masses of molten rock rise from deep inside Earth,

cool into a solid, travel along our planet’s surface and then sink back down. The process is known as plate

tectonics.

The term tectonics comes from a Greek word meaning “to build.” Tectonic plates are huge moving slabs that

together make up Earth’s outer layer. Some span thousands of kilometers (miles) on a side. In all, a dozen major

plates cover Earth’s surface.

You might think of them as the cracked eggshell jacketing a hard-boiled egg. Like an eggshell, plates are

relatively thin — on average only about 80 kilometers (50 miles) thick. But unlike an egg’s cracked shell,

tectonic plates travel. They migrate atop Earth’s mantle. Think of the mantle as the thick white part of a hard-

boiled egg.

Earth’s hot, liquid innards also are always in motion. That’s because warmer materials are generally less dense

than cooler ones, notes geologist Mark Behn. He's at the Woods Hole Oceanographic Institution in

Massachusetts. So, hot stuff in Earth’s middle “rises up — kind of like a lava lamp,” he explains. “Once it gets

back to the surface and cools off again, then it will sink back down.”

KEY WORDS

SUMMARY:

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Where tectonic plates meet, they can be pulling away from each other, pushing towards one another or sliding

past each other. These motions create mountains, earthquakes and volcanoes.

Jose F. Vigil/USGS/Wikimedia Commons

The rising of hot rock from the mantle to Earth’s surface is called upwelling. This process adds new material to

tectonic plates. Over time, the cooling outer crust becomes thicker and heavier. After millions of years, the

oldest, coolest parts of the plate sink back into the mantle, where they re-melt again.

“It’s like a giant conveyor belt,” explains geophysicist Kerry Key at the Scripps Institution of Oceanography.

It’s at the University of California, San Diego. That conveyer belt drives the movement of the plates. The

plates’ average speed is about 2.5 centimeters (roughly an inch) or so per year — about as fast as your

fingernails grow. Over millions of years, though, those centimeters add up.

So over eons, Earth’s surface has changed a lot. For instance, roughly 250 million years ago, Earth had one

giant landmass: Pangaea. Plate movement split Pangaea into two huge continents, called Laurasia and

Gondwanaland. As Earth’s plates kept moving, those landmasses each broke apart more. As they spread and

traveled, they evolved into our modern continents.

Although some people mistakenly talk about “continental drift,” it’s the plates that move. Continents are just the

tops of plates that rise above the ocean.

Moving plates can trigger huge impacts. “All the action is mostly at the edges,” notes Anne Egger. She’s a

geologist at Central Washington University in Ellensburg.

Colliding plates can crush against each other. Abutting edges rise as mountains. Volcanoes can form when one

plate slides beneath another. Upwelling also can create volcanoes. Plates sometimes slide past each other at

places known as faults. Usually these motions happen slowly. But large movements can trigger earthquakes.

And, of course, volcanoes and earthquakes can cause massive destruction.

The more scientists learn about plate tectonics, the better they can understand these phenomena. If scientists

could warn people when these events were coming, they also might help limit damage.

KEY WORDS:

SUMMARY:

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

P- wave =

S- wave =

Sound Waves

If a tree falls in the forest and no one is around to hear it,

does it make a sound?

As different as they are, all sounds have some things in common. One characteristic of sound is that it is

created by vibrations. A vibration is the complete back and forth motion of an object. Sound is transmitted

through the vibrations and collisions of particles of matter, such as air particles. Because the particles vibrate

back and forth along the paths that sound travels, sound travels as longitudinal waves.

Another characteristic of sound is that all sound waves require a medium. A medium is a substance through

which a wave can travel. In the example of a tree falling in the forest the medium is air. Most of the sounds

you hear travel through air at least part of the time. But sound waves can also travel through other materials,

such as water, glass and metal.

What would happen if a tree fell in outer space? No sound would be created because in space there are no air

particles to vibrate. Sound cannot travel there. The speed of sound also depends on the medium it travels

through. For example, sound traveling through the air moves slower than sound traveling through water; and

sound traveling through water moves slower than sound traveling through steel or glass.

Key words:

Summary:

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Guitar Lab

Question: What determines a sound’s pitch and loudness?

Materials:

Shoebox (or other small box)

Rubber bands of various sizes

Pencil

Tin cans

Beans of various sizes

Water

Procedure:

1. Stretch a rubber band lengthwise around the box and gently pluck the rubber band with your finger. Describe what you see

and hear in the table below.

2. Stretch another rubber band of a different thickness around the box, and pluck both rubber bands. Describe the difference

between the two sounds in the table below.

3. Put a pencil across the top of the box and under the rubber bands, and pluck again. Compare the sound with the sound you

heard before the pencil was used in the table below.

4. Move the pencil closer to one end of the box and pluck both sides of the pencil. Describe the difference in the sounds you

hear in the table below.

Trial Observations of sounds

Single rubber band

Two rubber bands

Rubber band with pencil

Pencil in new locations

5. Experiment!!! Use all sorts of materials to make sounds and describe them in the space provided. Can you make a sound

that is very loud? Very high frequency? Very low frequency? How do beans compare to rubber bands in the sounds they

make?

Trial (what did you use) Sketch Observations

Conclusion questions:

1. How did the thickness of the rubber bands affect the sound?

2. In steps 3 and 4 the pencil was used to shorten the part of the rubber band that was vibrating. What is

the relationship between shortened length and the sound you heard?

How the Ear Hears

1. The outer ear - The outer ear has three sections:

o The pinna or auricle: this is the part of the ear on the outside of our heads. The part we usually

are referring to when we say ear. It helps to gather sound and vibrations so we can hear more

sounds.

o The ear canal: This is a tube that helps sound to travel further inside our ear and to get to the next

stage of hearing

o The eardrum: The eardrum is a thin sheet that vibrates when the sound hits it. Your eardrum is

very sensitive and fragile. It's never a good idea to put anything in your ear, even something that

seems safe and soft can damage your eardrum.

2. The middle ear - The middle ear is filled mostly with air and has three bones in it. That's right your ear

has little bones called ossicles that help you hear! They are called the hammer (malleus), anvil (incus),

and stirrup (stapes). They amplify the sound or make it louder. The middle ear helps to transfer sounds

from the air to fluid inside the next stage, or inner ear. The stirrup is the smallest bone in the body.

3. The inner ear - The inner ear is filled with fluid and has the hearing organ called the cochlea. This

organ helps to take the vibrations and translate them into electrical signals for the nerve to send to the

brain. It actually uses little hairs that vibrate with the sound waves in the fluid. Then you "hear" it.

Amazing! The inner ear also has fluid filled tubes that help with your balance.

Reflection, Refraction, Diffraction and Absorption

Wave that reflect look like:

Waves that refract look like:

Waves that diffract look like:

Waves that are absorbed look like:

Light

An Electromagnetic Wave

Sum

Key

Key Points Questions

Sum It Up

The Electromagnetic Spectrum

Wave Type Definition Picture

Color

The color that an object appears to be is determined by the wavelengths of light that reach your eyes. Light

reaches your eyes after being reflected off an object or after being transmitted through an object. After reaching

your eyes, light is converted into electrical impulses and interpreted by your brain as colors.

Opaque objects: When white light strikes a colored opaque object, some colors of light are absorbed and some

are reflected. Only light that is reflected reaches your eyes and is detected.

Transparent objects: When light strikes a colored translucent object, you see the color of light that was

transmitted through the material. All the other colors were absorbed.

Mixing colors of light:

UV Lab

Question: Which sunscreen will protect from UV radiation the best?

Hypothesis: If___________________________________________________________________ I think

_____________________________________because______________________________________________

_________________________________________________________________________________________.

Rank the order in which you think the sunscreens will protect from UV light:

Most protective Least protective

Materials:

Black construction paper

Variety of sunscreens

Paintbrushes

Sun light

Procedure:

1. Cut 1 large piece of black construction paper into 6 equal sized rectangles.

2. On a tray lay out your paper pieces.

3. Using tape stick the construction paper to the tray and then label another piece of tape with the

sunscreen type and place it near the construction paper, so that every rectangle is labeled with a type

of sunscreen.

4. Using a clean paintbrush paint a full layer of each sunscreen on its rectangle of black paper on your

tray.

5. Clean your brush and complete all the rectangles with different types of sunscreen.

6. There should be one square with no sunscreen. This is your control.

7. Place your tray outside in the sunlight for 24 hours and then compare your results.

Results:

Which sunscreens actually worked the best? The worst?

Most protective Least protective

Conclusion questions:

1. Why do you think the most protective sunscreen was the best? Why did it protect from UV the most?

2. How is the experiment relate to sunscreen use for people?

3. In this experiment when the paper was exposed to the sun it got lighter, but when our skin is exposed

to the sun it often gets darker, why do you think we got the results we did in our experiment?

4. If you were to try this experiment again, what could you change to test something else about the

sunscreen? Could you use a different control?

Communicating with Waves Part 1-

Objective: Investigate different materials to make the best “paper cup” phone.

Materials:

Variety of cups

Variety of strings

Tape

Initial design:

Reflection: How well did it work? What would you change for next time?

Second design:

Reflection: How well did it work? What do you think the best improvement you made was?

Part 2-

All of our TV, computer, and cell phone images are composed of tiny picture elements called pixels. The more

pixels there are the sharper the image. For example consider the following images of the same photo but

made with more pixels on the left and less pixels on the right.

You can use a high power magnifier to see these on your own computer or TV screen. You’ll notice that each

pixel is made up of three tiny colored dots that make up all colors in the image.

Sending Messages:

SETI, the Search for Extraterrestrial Intelligence, is a scientific research project in which scientists “listen” for

radio or light signals that might be sent by other intelligent beings in the universe. One of the search

strategies is to figure out how a string of dots and dashes, or ones and zeros, could be interpreted as a

picture—perhaps of the life forms themselves. Such a string could be made visible if the ones were dark pixels

and the zeros were light pixels. But how would we know when one line ends and one begins?

Color the cells with 1’s in them to see the image:

0 0 0 0 0 0 0

0 0 0 0 0 0 0

0 1 0 1 0 1 0

0 1 0 1 0 0 0

0 1 0 1 0 1 0

0 1 1 1 0 1 0

0 1 0 1 0 1 0

0 1 0 1 0 1 0

0 1 0 1 0 1 0

0 0 0 0 0 0 0

0 0 0 0 0 0 0

Task: Your task is to work with team-mates to decide on a method of sending a string of 35 ones and zeros,

using sound, light, or some other method of sending a message across a large room. (35 is the product of two

prime numbers 7 and 5). Then you divide your team in half and go to opposite sides of the room. Each team

will use a 5 x 7 grid to make up a message to send to the other half of your team. To practice you might start

with a smaller set, say 15 characters making up a grid of 3 x 5 pixels.

Here is a 3 x 5 practice grid:

5 x 7 grid:

5x7 grid:

Reflection:

1. What are three different ways you could use to send a

message of 1’s and 0’s?

2. Are some solutions better than others? If so what is

better about them?

3. Sound and light are two different kinds of waves. How

do these methods use waves to communicate

information?

4. What are five different types of technology that use

waves to communicate information:

Practice Assignments

During each unit we study this year we will have time to practice the skills we are using

during class.

The assignments at the back of your packet must be completed before you take the unit

assessment.

You may choose to complete the practice assignments at home, during ELT, lunch, or

during “practice days” during class.

Your practice assignments for this unit are:

o Waves crossword puzzle( you will staple this into your packet)

o Study guide (this is already in your packet)

Study Guide

Sound and Light

In the space provided, write the letter of the term or phrase that best completes each statement or best

answers each question.

_____ 1. The intensity of a sound wave depends on a. the wave’s loudness.

b. the wave’s amplitude.

c. pitch.

d. frequency.

_____ 2. Resonance amplifies the sound of a guitar when the a. the guitar string and guitar body are both vibrating at the same frequency.

b. intensity of a sound decreases over time.

c. pitch of a note is compared with a pure tone.

d. vibration of a string or column of air causes a standing wave at a natural frequency.

_____ 3. Which property of light is not explained by the wave model of light? a. Light produces interference patterns.

b. Light is diffracted when it passes through a narrow opening.

c. Blue light can knock electrons off a plate but red light cannot.

d. Light reflects when it meets a mirror, but it refracts when it passes through a lens.

_____ 4. The rate at which light energy flows through a given area of space is referred to as its a. speed. c. intensity.

b. wavelength. d. energy.

_____ 5. Sonar and ultrasound technology depend on the ability of waves to a. reflect sound.

b. amplify sound.

c. disperse sound.

d. dissipate sound.

_____ 6. The law of reflection states that when light rays reflect off a surface, the angle of incidence a. is one-half the angle of reflection.

b. equals the angle of reflection.

c. is twice the angle of reflection.

d. equals the angle of refraction.

_____ 7. An image that results from the apparent path of light rays is called a(n) a. distorted image. c. objective image.

b. real image. d. virtual image.

_____ 8. Most musical instruments produce sound through the vibration of a. membranes.

b. air columns.

c. strings.

d. All of the above

_____ 9. The particle model of light explains how light can

a. travel through empty space without a medium.

b. refract when it passes through a lens.

c. be reflected off a mirror.

d. diffract when it passes through a normal opening.

_____ 10. The amount of energy in a photon of light is proportional to the a. medium through which it travels.

b. shape of the light wave it creates.

c. speed of the corresponding light wave.

d. frequency of the corresponding light wave.

_____ 11. When light rays reflect off a rough surface, they a. scatter in many different directions.

b. converge toward the normal.

c. diverge away from the normal.

d. decrease their speed and change their angle.

_____ 12. When you look at an orange, you see the color orange because the fruit a. reflects orange light and absorbs other colors.

b. absorbs orange light and reflects other colors.

c. reflects red and yellow light only.

d. absorbs red and yellow light only.

_____ 13. Which of the following uses radio waves to find an object’s location? a. sonar c. sonogram

b. ultrasound d. radar

_____ 14. Which structure within the eye is responsible for the largest percentage of refraction of light? a. retina c. lens

b. cornea d. iris

_____ 15. White light separates into different colors when it passes through a prism because of a. differences in wave speed. c. reflection.

b. total internal dispersion. d. droplets in the air.

_____ 16. If you looked at a red tulip with green leaves under green light, you would see a a. green tulip with green leaves.

b. black tulip with green leaves.

c. yellow tulip with black leaves.

d. black tulip with black leaves.

_____ 17. A virtual image caused by reflection of light in the atmosphere is called a a. prism. c. mirror.

b. lens. d. mirage.

_____ 18. Which statement about a diverging lens is correct? a. It bends light inward and can create either a virtual or a real image.

b. It bends light inward and can only create a real image.

c. It bends light outward and can create either a virtual or a real image.

d. It bends light outward and can only create a virtual image.

_____ 19. The effect in which white light separates into different colors is called a. magnification. c. reflection.

b. refraction. d. dispersion.

_____ 20. Sonar and ultrasound technology depend on the ability of waves to a. reflect sound.

b. amplify sound.

c. disperse sound.

d. dissipate sound.

Read each statement, and write in the blank the word or words that best completes the statement.

21. The greater the _______________________ of a sound wave, the louder the

sound.

22. Reflected sound waves make it possible for _______________________

devices to measure distance.

23. The three small bones in your middle ear are the _______________________, the

_______________________, and the _______________________.

24. In the particle model of light, individual “packets” of light are called

_______________________.

25. Radio waves, microwaves, and infrared waves make up a part of the

_______________________.

26. The theoretical line perpendicular to the surface where a light ray hits a mirror

is called the _______________________.

27. When you look into a flat mirror, you see a(n) _____________image.

28. When sunlight is dispersed and reflected by water droplets, a(n)_____ ________ forms.

29. If light moves from a material in which its speed is lower to one in which its speed is higher, the ray is bent away from the ____________________.

30. An object looks red to your eye if it _______________________ red light and

_______________________ all other colors.

31. Light waves _______________________ when they pass from one transparent medium to another.

32. Sound will travel more quickly through air if the _______________________ of the air increases.

33. In your inner ear, different parts of the _______________________ vibrate at

different natural frequencies.

34. Sound waves with frequencies higher than 20,000 Hz are referred to as

_______________________ waves.

35. The two most common models of light describe it as a wave or as a stream of

_______________________.

36. All possible kinds of light, at all energies, frequencies, and wavelengths, make

up the _______________________.

37. Reflection of light in random directions is called _______________________.

38. A mirror that curves outward is a(n) _______________________ mirror.

Short Answer

1. Describe two different forms of electromagnetic waves and explain their uses in technology.

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

2.Explain why the speed of sound changes if the temperature of the medium changes.

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

3. Determine which band of the electromagnetic spectrum has each of the following:

_____________________ a. the longest wavelength

_____________________ b. the highest frequency

_____________________ c. the greatest energy

_____________________ d. the least energy

4.Use the law of reflection to draw a sketch showing the incoming and reflected light rays when light shines on a mirror at an angle of 30° to the normal. Label the angle of incidence and the angle of reflection.

5.List the colors in the visible spectrum in order from longest to shortest wavelength.

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________