Name________________________________________Period__________Date____________________
WAVES, SOUND, LIGHT, HEAT TEST REVIEW
1. What does the wavelength of a wave indicate?
The energy of the wave: long wavelengths and low frequencies have lower energy than
shorter wavelengths with high frequencies.
2. How are sound and light waves different?
a) Sound are longitudinal; travel slower at 300 meters/sec than light waves; need a
medium for the energy to travel through.
b) Light waves are transverse, travel faster than sound waves at 300,000,000 meters/sec;
and can travel through empty space.
3. What does white light traveling through a prism reveal?
All the colors of the visible spectrum, arranged by wavelength!
4. What happens to the speed of sound waves as they travel from air into water?
The speed of sound increases because the water is denser.
5. What happens to the speed of sound waves as air temperature increases?
When the air temperature increases the speed of sound increases because the molecules of
air move faster which means they can transfer the vibrations quicker.
6. What type of wave travels the fastest?
Light = 300,000,000 meters/sec (compared to sound in air at 300 meters/sec)
7. What happens to the noise level of a sound wave as the amplitude increases?
As the amplitude increases, the energy level increases so we hear a LOUDER sound.
Use the figures below to answer the next 3 questions. All pictures are drawn to the same scale
Figure 1
Figure 2
8. Which one has the greatest amplitude?
Figure 4
9. Which one has the highest frequency?
Figure 3
10. Which one has the longest wavelength?
Figure 1
Figure 3
Figure 4
Use the chart below to answer the next 2 questions
SUBSTANCE
Air at 25C
Water at 25C
Steel
SPEED
346 m/s
1498 m/s
5200 m/s
11. What is the relationship between the speed of sound and the density of the substance it
travels through?
The denser the material the faster the speed of sound.
12. What will happen to sound waves traveling through the air when they reach
water? Sound waves will speed up when they go from air into water because the
water is denser. The molecules in a denser material are closer together so pass
along the sound vibrations quicker.
13. Why does the spoon in the glass of water look like it is bent?
Light changes speed as it travels from air into the glass. As it changes speeds it also bends!
The result the spoon looks broken.
Use this information to answer the next two questions:
Two students wish to measure the speed of sound in water. They go to one end of a swimming
pool and strike a bell with a hammer underwater. They time how long it takes for the sound to
reach the other end of the pool. This table shows their data:
TRIAL
TIME
seconds
1
.12
2
.15
3
.08
4
.11
5
.12
6
.09
7
.10
8
.18
9
.13
10
.12
14. Why did the students do 10 trials instead of 1?
More trials increases the accuracy of the result. In this case you would take the average of
the trials to get your result.
15. You can estimate how far away a lightning bolt strikes by counting the seconds between
seeing the lightning and hearing the thunder. Why does this work?
Light travels much faster than sound, so you see the lightning first and then hear the
thunder, generally five seconds for each mile away.
Students use a light meter to measure the intensity of the light from a light. They start close to
the light and then move away one meter at a time.
16. What would you expect to happen to the amount of light energy the meter senses as you
move away from the light?
The light energy decreases as you move away from the source.
17. How are a raindrop and a glass prism alike?
They both split (refract) light into a rainbow of color
arranged by wavelength.
Use this picture to answer the next three questions:
18. What type of heat transfer is taking place at point A?
Convection – moving water
19. What type of heat transfer is taking place at point B?
Conduction – handle becomes hot to touch
20. What type of heat transfer is taking place at point C?
Radiation – infrared waves from the fire
21. How is the heat transfer process at “B” different than at “A”? Heat is transferred by
touching at point B – conduction. The heated water at point A moves up pushing the cooler
water at the top down to the bottom to heat – convection.
22. What is another example of the process at “A”?
Convection: Wind is created by heated air – hot air rises which pushes the cold air down!
23. What is another example of the process at “B”?
Conduction: Waxing a snowboard uses an iron directly touching the wax to melt it.
24. What is another example of the process at “C”?
Radiation: a heating lamp in an incubator
25. How do humans most often sense light energy?
With their eyes!
26. How do humans most often sense heat energy?
With their skin!
27. A snake comes out of its hole in the morning and warms itself on a rock. What has the snake
responded to?
It has responded to the heat energy in the rock transferred to his body by conduction.
28. How do plants respond to light?
The leaves will turn towards the light! They will follow the light.
29. The following circles represent the diameters of tubes all the same length. Put them in
order (1 to 5) according to the sound they produced, beginning with the lowest sound (1) to
the highest sound (5). Write the number inside the circle.
2
4
3
1
5
30. List the colors of light from longest wavelength to shortest.
Red, Orange, Yellow, Green, Blue, Indigo, Violet (ROY G. BIV)
Define the following energies and give an example of each:
TYPE OF ENERGY
31. Light or Radiant Energy
32. Thermal Energy
33. Sound Energy
DEFINITION
Energy carried by
electromagnetic waves
Sum of KE and PE of the
particles that make up
an object
Energy produced by
vibrations of particles
EXAMPLE
Sun light
Light bulb; microwave
Fire heating the air;
Iron, Lava Lamp
Playing the organ,
Singing a song
34. The shorter the wavelength the (lower,higher) the frequency.
35. Radio waves have a (lower, higher) frequency than gamma rays.
36. List the colors of light from longest wavelength to shortest.
Red, Orange, Yellow, Green, Blue, Indigo, Violet (ROY G. BIV)
37. What type of heat would you use to bake a pie?
Conduction – pie crust touching the metal pie tin!
38. What type of heat would you use to make pancakes? Conduction – touching the griddle!
39. What is the energy transfer that is going on in the sun? (Need 3 different energies)
1. Nuclear Energy: nuclear fusion taking place where hydrogen atoms are combining to make helium
atoms; a lot of energy is released in the process!
2. Radiant energy: the energy released during the nuclear reaction travels to the earth in the form of
electromagnetic waves, including visible light waves!
3. Thermal/Heat energy: Radiant energy increases the motion of molecules which increases the kinetic
energy of the molecules!
4. Match the following with the correct type of heat transfer and list 2 examples of each
(conduction, convection, radiation)
TYPE OF HEAT
DEFINITION
Conduction
Touching
Radiation
Not touching
Convection
Moving
EXAMPLES
1) Using a curling iron
2) Heating soup on the
stove
1) Using a microwave
2) Turning on a light
1) Heating system in a
home
2) Hot air balloon rising
floating up!