PHYSICAL SCIENCE
Waves, Light, and Sound Unit
Day 1: Objectives 18.1.1, 18.1.2
Before class: Read section 18 – 1
Answer the following. Complete sentences are not needed.
1. What do waves transfer?
2. In what unit is frequency usually expressed?
3. What happens to the wavelength if the frequency increases?
4. What are the highest points on a wave?
After class:
Use words from section 18-1 to write the words that fill in the blanks in the passage below. Note that some of the blanks are filled in already. All your answers need to be written on your own paper, not on this sheet.
Waves are rhythmic disturbances. The easiest type of wave to visualize is a (1.) ______e __ wave. (2.) E ______transfer energy in powerful shock waves that (3.) t ______through Earth. Most waves travel through some kind of material called a
(4.) __ e ______. However, two types of waves that can travel without any special material present are radio waves and (5.) __ __ g __ __ waves.
You can produces (6.) __ __ a ______waves in a rope by snapping it up and down. The highest points of such waves are called
(7.) __ r ______s, and the lowest points are called (8.) __ r ______s . The distance between the high point of one wave and the high point of the next wave is the (9.) w ______n ______. The distance from the crest of a wave to the rest position of the medium is the
(10.) a ______of the wave. The number of wave crests that pass a place in one second is called the (11.) f ______n __ __ o f the wave, which is expressed in units called(12.) __ __ r __ __.
13. On graph paper, draw a wave that has a wavelength of 4 units and an amplitude of 2 units. (Each square represents one unit.)
14. On graph paper, draw a wave that has a wavelength of 8 units and an amplitude of 4 units.
15. On graph paper, draw a wave that has a wavelength of 4 units and an amplitude of 2 units.
Day 2: Objectives 18.1.3
Before class: Read section 18 – 1
Answer the following. Complete sentences are not needed.
1. Describe the relationship between frequency and wavelength.
During class:
1. Practice: A wave is generated in a wave pool at a water park. The wavelength is 3.2 m. The frequency is 0.60 Hz. What is the velocity of the wave?
2. Practice: A wave moving along a rope has a wavelength of 1.2 m and a frequency of 4.5 Hz. How fast is the wave traveling along the rope?
3. Practice: Earthquakes can produce a transverse wave that travels at 5000 m/s. its wavelength is about 417 m. What is its frequency?
4. Practice: A tuning fork produces a sound wave with a wavelength of 0.20 m and a velocity of 25.6 m/s. What is the frequency of the tuning fork?
5. Practice: A tuning fork produces a sound wave with a frequency of 122 Hz and a velocity of 343 m/s. What is the wavelength of the wave?
6. Practice: A tuning fork produces a sound wave with a frequency of 252 Hz and a velocity of 343 m/s. What is the wavelength of the wave?
After class:
1. A wave moving along a rope travels at a velocity of 4.0 m/s and has a frequency of 3.5 Hz. What is the wavelength? Show your work.
2. Sketch a transverse wave. On the wave, label a crest, a trough, a wavelength, and the amplitude.
3. Using information from section 18 – 1, consider the wavelength, frequency, and amplitude of a wave.
a. Which of these measurements depend(s) on energy?
b. Which of these measurements is/are measured in meters?
c. Which of these measurements depend(s) on the number of wave crests?
Answer the following using complete sentences.
4. FM radio stations send out frequencies in the megahertz (MHz) range. (1 MHz = 1,000,000 Hz) Suppose your favorite radio station is
100.1 MHz on the FM dial and your friend prefers a station that tunes in at 107.7 MHz. Whose station sends out waves of longer wavelength? Explain your answer.
Day 3: Objectives 18.2.1, 18.2.2, 18.2.3, 18.2.4
Before class: Read section 18 – 2
Answer the following. Complete sentences are not needed.
1. What is the relationship between frequency and pitch?
2. The amount of energy in a sound wave determines its ______and its ______.
3. Can sound travel through empty space?
4. What is the Doppler effect?
After class:
1. What type of waves are sound wavers and how do they transfer energy?
2. How does the temperature of the medium affect the speed of sound waves?
3. While on your way to school, you turned up the volume on the car radio. Which of the following quantities changes as a result: velocity of sound, intensity, pitch, frequency, wavelength, loudness?
4. While watching a “Star Trek” rerun, you hear the roaring approach of another ship in space. Is this possible? Explain your answer.
5. A bat in a dark cave sends out a high frequency sound wave and detects an increase in frequency after the sound reflects off the prey. Is the bat flying towards the prey or away from it?
Day 4: Objective 18.2.3
Before class:
Answer the following. Complete sentences are not needed.
1. Describe the relationship between frequency and pitch.
During class:
Perform the following lab.
Materials:
PVC pipe of 3 different lengths
pencil
meterstick
Procedure:
1. Measure the length of a pipe and record it in the data table.
2. Hold on end of the pipe up to your ear. Tap the other end of the pipe with your pencil.
3. Repeat steps 1 and 2 for two more pipes.
4. Observe which pipe has the highest pitch and which has the lowest pitch.
Data and observations:
Sound Frequencies produced by open pipesLength of Pipe (cm) / Wavelength of sound (cm) / Frequency of sound (Hz)
1. The wavelength of the pipe is twice the length of the pipe. Calculate the wavelength for each pipe and record it in the data table. Show your work.
2. Assume the velocity of sound to be 34 200 cm/s. Calculate the frequency of the note from each pipe. Record it in the data table. Show your work.
After class:
Answer the following using complete sentences.
3. How does the length of a pipe compare with the frequency and wavelength of the sound it can make?
4. Do higher or lower frequencies have higher pitches?
5. A pipe organ uses pipes of different lengths to produce various notes. What other musical instruments use lengths of pipe to produce musical notes?
Matching: Write the letter for the item in Column II for the number of each phrase in Column I. (not all answers will be used)
PHYSICAL SCIENCE
Waves, Light, and Sound Unit
6. _____sounds move fastest in these media
7. _____apparent change in pitch of a sound caused by the motion of the object making the sound
8. _____sounds with frequencies too low for the human ear to hear
9. ____area of a sound wave where particles are squeezed close together
10. ____human perception of loudness
11. ____condition of a medium that affects the speed at which a sound wave travels
12. ____produce sounds
13. ____matter vibrates in the same direction as these waves travel
14. ____vibrate when you talk
15. ____unit of sound intensity
16. ____area of a sound wave where particles are less dense
17. ____frequencies too high-pitched for the human ear to hear
18. ____the highness or lowness of a sound
19. ____distance between two side by side compressions of the same wave
20. ____number of compressions that pass a place each second
a. amplitude
b. compression
c. compressional waves
d. crests
e. Doppler effect
f. frequency
g. gases
h. infrasonic
i. intensity
j. liquids
k. decibel
l. pitch
m. rarefaction
n. temperature
o. transverse waves
p. troughs
q. solids
r. ultrasonic
s. vibrations
t. vocal cords
u. wavelength
PHYSICAL SCIENCE
Waves, Sound, and Light Unit
Day 5: Objectives 18.4.1, 18.4.2, 18.4.3
Before class: Read section 18 – 4
Answer the following. Complete sentences are not needed.
1. Two different instruments that play at the same pitch and loudness have different ______.
2. What is sound with no set pattern and no definite pitch?
3. ______occurs whn two or more waves combine to form a new wave.
4. ______is caused when the same sound reaches the same place at several different times.
After class:
Answer the following using complete sentences.
1. Compare and contrast music and noise.
2. If you were to close your eyes and listen to middle C played both on a piano and on a cello, what musical property would enable you to distinguish one instrument from the other?
3. Compare and contrast constructive and destructive interference.
4. Intense high frequency sound can actually cause glass to shatter. What is happening to the glass that causes it to break?
Day 6: Objectives 19.1.1, 19.1.2, 19.1.3
Before class: Read pages 484 - 488
Answer the following. Complete sentences are not needed.
1. What do radio waves, microwaves, x-rays, and visible light all have in common?
2. Define:
a. radiation
b. electromagnetic spectrum
c. photons
After class:
Answer the following using complete sentences.
1. Describe at least three ways electromagnetic waves differ from sound waves.
2. Arrange the following waves in order of decreasing wavelength: radio waves, gamma rays, ultraviolet rays, visible light, infrared radiation.
3. How do microwaves cook food?
4. Explain whether or not you can hear radio waves.
Day 7: Objectives 19.1.2, 19.1.3, 19.2.1, 19.2.2
Before class: Read pages 488 – 493
Answer the following. Complete sentences are not needed.
1. What type of electromagnetic waves have the highest frequency?
2. What type of electromagnetic waves have the longest wavelength?
3. Define:
a. opaque materials
b. transparent materials
c. translucent materials
After class:
Answer the following using complete sentences.
1. Explain how X rays can be used to photograph your bones.
2. If someone told you that you were being exposed to radio waves and gamma radiation, which would you be the most concerned about? Explain your answer.
3. Contrast opaque, transparent, and translucent materials. Give at least one example of each.
4. Outline the major types of electromagnetic radiation discussed in section 19 – 1. Include at least two uses for each type. If you need help making an outline, refer to page 677.
Day 8: Objectives 19.4.1, 19.4.2, 19.4.3
Before class: Read section 19 – 4
Answer the following. Complete sentences are not needed.
1. What is it called when waves bend due to a change in their speed?>
2. A line drawn perpendicular to the surface of the barrier is the ______.
3. What is the bending of light waves around a barrier?
4. ______is caused when light waves overlap each other.
5. Define: diffraction grating
After class:
Answer the following using complete sentences.
1. Explain the law of reflection.
2. When light moves from air into glass at an angle, is the light refracted toward or away from the normal?
3. Explain how a prism separates the colors of the spectrum from white light.
4. Scientists say that light has both particle and wave properties. Explain why observations of diffraction and interference patterns conflict with the idea that light consists of particles.
Day 9: Objectives 20.1.1, 20.1.2
Before class: Read section 20 – 1
Answer the following. Complete sentences are not needed.
1. A ______forms an upright, virtual image.
2. A ______is curved like the inside of a spoon.
3. What image do you see if you place the object at the focal point of a concave mirror?
4. Define: a. virtual image; b. focal point; c. focal length; d. real image
After class: Use the terms in the list to fill in the blanks in the paragraph about mirrors. Two terms will be used twice.
PHYSICAL SCIENCE
Waves, Sound, and Light Unit
reversed
reflect
virtual
smooth
behind
plane
eyes
ray
length
concave
convex
real
focal
optical
spread
smaller
upside down
upright
PHYSICAL SCIENCE
Waves, Sound, and Light Unit
Mirrors can be formed by almost any ______surface. Flat mirrors made from glass with a reflective coating on the back are called ______mirrors. To see your face in a mirror, light has to ______off your face. This light goes to the mirror and is reflected toward your ______. The image you see will be ______from left to right. To explain this requires the use of a ______model. The image will appear to come from ______the mirror. Since there is nothing behind the mirror, this image is called a ______image.
Mirrors that have a curve like the bowl of a spoon are called ______mirrors. A straight line going through the center of a mirror is called the ______axis. Beams of light parallel to this axis will strike a concave mirror and be reflected to pass trhough a point on the optical axis called the ______point. The distance from the focal point to the center of the mirror is called the focal ______. When a concave mirror is used to reflect light from an object that is placed farther from the mirror than the focal point, the image formed will be a ______image. the image will be enlarged and ______. If the object is placed between the focal point and the mirror, an image is seen that is enlarged, ______, and seems to be ______the mirror. Because the image appears to be behind the mirror, it cannot be projected onto a screen like a real image and is therefore called a ______image.
A type of mirror like the back of a spoon is called a ______mirror. The rays that are reflected from this mirror are always ______out. When this happens, the image will appear to be behind the mirror and be upright but ______than the original object.
Day 10: Objectives 20.2.1, 20.2.2, 20.2.3
Before class: Read section 20 – 2
Answer the following. Complete sentences are not needed.
1. A(n)______lens causes light rays to diverge.