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1 | |
(a) Distinguish between longitudinal and transverse waves. (b) Do all waves fall into one or the other of these categories? If not, give an example of one that does not. |
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2 | |
Does increasing the frequency of a wave also increase its wavelength? If not, how are these quantities related? |
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3 | |
Why does sound travel fastest in solids and slowest in gases? |
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4 | |
The speed of sound in a gas depends upon the average speed of the gas molecules. Why is such a relationship reasonable? |
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5 | |
What types of waves can be refracted? Under what circumstances does refraction occur? |
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6 | |
What eventually becomes of the energy of sound waves? |
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7 | |
Even if astronauts on the moon's surface did not need to be enclosed in space suits, they could not speak directly to each other but would have to communicate by radio. Can you think of the reason? |
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8 | |
(a) You are standing on a pier and want to spear a fish that swims by. Should you aim above, below, or exactly where the fish seems to be? (b) What if you are swimming underwater and want to spear a fish? |
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9 | |
In what unit is the loudness of a sound expressed? |
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10 | |
How can constructive and destructive interference be reconciled with the principle of conservation of energy? |
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11 | |
In what kinds of waves can the Doppler effect occur? |
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12 | |
A "double star" consists of two nearby stars that revolve around their center of mass (see Sec. 1-10). How can an astronomer recognize a double star from the characteristic frequencies of the light that reaches him from its member stars? |
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13 | |
If you walk past a bell while it is ringing, you notice no change in pitch, but if you ride past the same bell in a rapidly moving train or car the pitch seems to change markedly. Explain. |
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14 | |
Why are light waves able to travel through a vacuum whereas sound waves cannot? |
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15 | |
How could you show that light carries energy? |
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16 | |
Why was electromagnetic induction discovered much earlier than its converse, the production of a magnetic field by a changing electric field? |
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17 | |
Light is said to be a transverse wave. What is it that varies at right angles to the direction in which a light wave travels? |
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18 | |
How are the directions of the electric and magnetic fields of an em wave related to each other and to the direction in which the wave is moving? |
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19 | |
Light waves carry both energy and momentum. Why doesn't the momentum of the sun diminish with time as its energy content does? |
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20 | |
Give as many similarities and differences as you can between sound and light waves. |
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21 | |
The period of daylight is increased by a small amount because of the refraction of sunlight by the earth's atmosphere. Show with the help of a diagram how this effect comes about. |
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22 | |
When a fish looks up through the water surface at an object in the air, will the object appear to be its normal size and distance above the water? Use a diagram to explain your answer, and assume that the fish's eye and brain, like the human eye and brain, are accustomed to interpreting light rays as straight lines. |
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23 | |
What is the height of the smallest mirror in which you could see yourself at full length? Use a diagram to explain your answer. Does it matter how far away you are? |
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24 | |
Does a spherical bubble in a pane of glass act to converge or diverge light passing through it? |
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25 | |
Does a lens opening of f/8 let more or less light reach the film of a camera than one of f/16? |
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26 | |
When white light is dispersed by a glass prism, red light is bent least and violet light is bent most. What does this tell you about the relative speeds of red and violet light in glass? |
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27 | |
When a beam of white light passes perpendicularly through a flat pane of glass, it is not dispersed into a spectrum. Why not? |
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28 | |
What color would red cloth appear if it were illuminated by (a) white light? (b) red light? (c) green light? |
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29 | |
(a) What would the American flag look like when viewed with red light? (b) With blue light? |
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30 | |
Light of what color is scattered most in the atmosphere? Least? |
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31 | |
If the earth had no atmosphere, what would the color of the sky be during the day? |
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32 | |
Give two advantages that a telescope lens or mirror of large diameter has over one of small diameter. |
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33 | |
Radio waves are able to diffract readily around buildings, as anybody with a portable radio receiver can verify. However, light waves, which are also electromagnetic waves, undergo no discernible diffraction around buildings. Why not? |
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