If the path-length difference between two identical and

According to Huygens, how does every point on a wavefront behave?

Will plane waves incident upon a small opening in a barrier fan out on the other side or continue on as plane waves?

Is diffraction more pronounced through a small opening or through a large opening?

For an opening of a given size, is diffraction more pronounced for a longer wavelength or for a shorter wavelength?

Which more easily diffracts around buildings: AM or FM radio waves? Why?

Is interference restricted to only some types of waves, or does it occur for all types of waves?

What aspect of light did Thomas Young demonstrate in his famous light experiment?

What accounts for the light and dark bands that are produced when monochromatic light reflects from a glass plate atop another glass plate?

What is meant by saying that a surface is optically flat?

What is the cause of Newton’s rings?

What causes the spectrum of colors seen in gasoline splotches on a wet street? Why aren’t these splotches seen on a dry street?

What produces iridescence?

What accounts for the different colors in either a soap bubble or a layer of gasoline on water?

Why are interference colors primarily cyan, magenta, and yellow?

What phenomenon distinguishes longitudinal waves from transverse waves?

How does the direction of polarization of light compare with the direction of vibration of the electron that produces it?

Why will light pass through a pair of Polaroids when the axes are aligned but not when the axes are at right angles to each other?

How much ordinary light will an ideal Polaroid transmit?

When ordinary light is incident at an oblique angle upon water, what can you say about the reflected light?

Does parallax underlie the depth perceived in stereo views?

Is parallax evident when you close one eye?

Would the viewer perceive depth if the images being projected in Figure \(29.40\) were identical? Equation Transcription: Text Transcription: \(29.40\)

What role do polarization filters play in 3-D projection?

How does a hologram differ from a conventional photograph?

Why can sunlight that illuminates Earth be approximated by plane waves, whereas the light from a nearby lamp cannot?

Why do radio waves diffract around buildings but light waves do not?

In our everyday environment, diffraction is much more evident for sound waves than for light waves. Why is this so?

How are interference fringes of light analogous to the varying intensity that you hear as you walk past a pair of speakers that are emitting the same sound?

By how much should a pair of light rays from a common source differ in distance traveled to produce destructive interference?

Light illuminates two closely spaced thin slits and produces an interference pattern on a screen behind. For which color of light—yellow or green—will the distance between the fringes be greater?

A double-slit arrangement produces interference fringes for yellow sodium light. Should red light or blue light be used to produce narrower-spaced fringes?

When the reflected path from one surface of a thin film is one full wavelength different in length from the reflected path from the other surface and no phase change occurs, will the result be destructive interference or constructive interference?

When the reflected path from one surface of a thin film is one-half wavelength different in length from the reflected path from the other surface and no phase change occurs, will the result be destructive interference or constructive interference?

Suppose you place a diffraction grating in front of a camera lens and take a picture of illuminated streetlights. What will you expect to see in your photograph?

What happens to the distance between interference fringes if the separation between two slits is increased?

Why is Young’s experiment more effective with slits than with the pinholes he first used?

In which of these is color formed by refraction: flower petals, rainbows, soap bubbles? By selective reflection? By thin-film interference?

The colors of peacocks and hummingbirds are the result not of pigments but of ridges in the surface layers of their feathers. By what physical principle do these ridges produce colors?

The colored wings of many butterflies are due to pigmentation, but in others, such as the Morpho butterfly, the colors do not result from any pigmentation. When the wing is viewed from different angles, the colors change. How are these colors produced?

Why do the iridescent colors seen in some seashells (such as abalone shells) change as the shells are viewed from various positions?

When dishes are not properly rinsed after washing, different colors are reflected from their surfaces. Explain.

Why are interference colors more apparent for thin films than for thick films?

Will the light from two very close stars produce an interference pattern? Explain.

If you notice the interference patterns of a thin film of oil or gasoline on water, you’ll see that the colors form complete rings. How are these rings similar to the lines of equal elevation on a contour map?

Because of wave interference, a film of oil on water in sunlight is seen to be yellow to observers directly above in an airplane. What color of light transmits through the oil (that would be seen by a scuba diver directly below)?

For the Hubble Telescope, which light—red, green, blue, or ultraviolet—is better for seeing fine details of distant astronomical objects?

Polarized light is a part of nature, but polarized sound is not. Why?

Why will an ideal Polaroid filter transmit 50% of incident nonpolarized light?

Why may an ideal Polaroid filter transmit anything from zero to 100% of incident polarized light?

How can you determine the polarization axis for a single sheet of Polaroid (especially if you’re at the edge of a lake)?

What percentage of light is transmitted by two ideal Polaroids, one on top of the other with their polarization axes aligned? With their axes at right angles to each other?

Why do Polaroid sunglasses reduce glare, whereas nonpolarized sunglasses simply cut down the total amount of light reaching the eyes?

To remove the glare of light from a polished floor, should the axis of a Polaroid filter be horizontal or vertical?

Most of the glare from nonmetallic surfaces is polarized, with the axis of polarization parallel to the axis of the reflecting surface. Would you expect the polarization axis of Polaroid sunglasses to be horizontal or vertical? Why?

How can a single sheet of Polaroid film be used to show that the sky is partially polarized? (Interestingly enough, unlike humans, bees and many insects can discern polarized light and use this ability for navigation.)

Why did practical holography have to await the advent of the laser?

When white light diffracts upon passing through a thin slit, as in Figure 29.8b, different color components diffract by different amounts so that a rainbow of colors appears at the edge of the pattern. Which color is diffracted through the greatest angle? Which color through the smallest angle?

Which of these is most central to holography: interference, selective reflection, refraction, or all of these?

Which will give wider-spaced fringes in a double-slit experiment: red light or violet light? (Let Figure 29.18 guide your thinking.)

Which will give wider-spaced fringes: a double-slit experiment in air or in water? (Let Figure 29.18 guide your thinking.)

If the path-length difference between two identical and coherent beams is two wavelengths when they arrive on a screen, will they produce a dark or a bright spot?

Which will produce more widely spaced fringes of light when passed through a diffraction grating: light from a red laser or light from a green laser?

The digital displays of watches and other devices are normally polarized. What related problem can occur when you are wearing Polaroid sunglasses?

Light will not pass through a pair of Polaroid sheets when they are aligned perpendicularly. However, if a third Polaroid is sandwiched between the two with its alignment halfway between the alignments of the other two (that is, with its axis making a \(45^{\circ}\) angle with each of the other two alignment axes, as in Figure 29.34), some light does get through. Why? Text Transcription: 45^circ