Physics for Future Presidents Chapter 8

Sunglasses can help you see a fish underwater because A. reflected light is polarized B. light from the fish is polarized C. the dim the light making your pupils dilate D. they cut the blue light of the water surface

A. reflected light is polarized

An indication that light is a wave is (choose all that are appropriate) A. that it has dark bands in the diffraction pattern B. that it passes through glass C. that it reflects off surfaces D. its high speed

A. that it has dark bands in the diffraction pattern

In the pinhole camera, more blurring occurs if A. the hole is made very large (but not if it is very small) B. the hole is made very small (but not if it is made very large) C. the hole is either very large or very small D. Never, since there is no lens in a pinhole camera.

A. the hole is made very large (but not if it is very small)

Light is polarized when it bounces off (choose all that are correct) A. water B. glass C. air

A. water B. glass C. air

If c is the speed of light in vacuum, then the speed of light in glass is approximately A. 1.5 c B. (2/3) c C. c D. .999 c

B. (2/3) c

The wavelength of visible light is closest to the diameter of A. a human hair B. a red blood cell C. an atom D. a. nucleus

B. a red blood cell

In one millionth of a second, light will travel (caution: probably a trick question) A. about 1 foot B. about 1000 feet C. from one side of a computer chip to the other D. from the earth to the moon

B. about 1000 feet

A successful fisherman will throw the spear A. above the fish image B. below the fish image C. right at the fish image D. it depends on how close the fish is

B. below the fish image

Rainbows show different colors because A. droplets of water have different sizes B. in water, different frequencies have different velocities C. the direction of light "spreads" because the wavelength is short D. droplets of water change the color of air molecules

B. in water, different frequencies have different velocities

As the wavelength of light decreases, the frequency A. decreases B. increases C. stays the same

B. increases

The index of refraction measures A. the frequency of light B. the speed of light C. the period of light D. density of the glass

B. the speed of light

Polaroids are used fro 3-D movies because A. they reduce glare from the surface B. they give a different image to each eye C. they polarize the light D. they reduce the dispersion

B. they give a different image to each eye

Light waves are A. longitudinal B. transverse C. circular

B. transverse

Your eye has A. one lens, called the lens B. two lenses-the lens and the cornea C. two lenses-the lens and the retina D. no lenses, but behaves like a pinhole camera

B. two lenses-the lens and the cornea

Light in a vacuum goes 1 foot every nanosecond (billionth of a second). In water, in one nanosecond it will go about A. 1 foot B. 1.5 feet C. .66 foot D. 0 feet (light doesn't travel through water)

C. .66 foot

For a good telescope (like Hubble) in geosynchronous orbit (HEO), a typical resolution is about A. 4 inches B. 3 feet (about 1 meter) C. 20 feet D. 300 feet

C. 20 feet

The Keck uses what to focus light? A. computers B. a lens C. a mirror D. it doesn't focus light

C. a mirror

Which of the following has the lowest index of refraction? A. water B. glass C. air D. crystal

C. air

Which color of light would give the highest number of bits per second in fiber? A. red B. white C. blue D. infrared

C. blue

A piece of glass is shaped like a pyramid. The side of the pyramid is tilted at 45 degrees with respect to the horizontal. A beam of light is inside the glass, moving horizontally. When it emerges from the tilted surface of the glass, it will be moving A. perfectly horizontal B. in a direction that is tilted upward (so it will eventually go into space) C. in a direction that is tilted downward (so it will eventually hit the ground)

C. in a direction that is tilted downward (so it will eventually hit the ground)

Holograms depend on the fact that light A. contains red, green, and blue B. is quantized C. is a wave D. can be focused

C. is a wave

The Keck telescope is "powerful" because A. it gives larger magnification B. it can use UV light C. it has a bigger mirror to collect light D. it has a bigger focal length than others

C. it has a bigger mirror to collect light

Old people need reading glasses because their A. pupils can't contract as well B. eyes become less sensitive to visible light C. lenses become less flexible D. they forget how to read

C. lenses become less flexible

Red-eye in photographs comes from A. the film detecting IR B. poor focus on the eye C. light of the flash reflecting off the retina (the back of the eye) D. light of the flash reflecting off the cornea (the surface of the eye)

C. light of the flash reflecting off the retina (the back of the eye)

People squint to see better because squinting A. reduces the light B. bends the lens to make it stronger C. reduces the blur size D. They don't see better. They only think that they do.

C. reduces the blur size

To make a spy satellite that can read a license plate, you would have to A. put it in a higher orbit B. cover it with a polarizing filter C. use a larger mirror D. Do nothing; they already can read license plates

C. use a larger mirror

The resolution of a human eye is about A. 4 mm B. 2 cm C. 1 micron D. 1/60 degree

D. 1/60 degree

Two soap bubbles from the same soap appear to be different colors. They probably have A. different sizes B. different absorption C. different temperature D. different thickness

D. different thickness

The human eye has cones that detect A. red, yellow, blue B. cyan, magenta, yellow C. yellow, green, red D. green, blue, red

D. green, blue, red

When we say a man is color blind, we usually mean that A. everything looks black and white (or gray) B. unlike others, he can't see ultraviolet or infrared C. he can sense only three colors D. he can't distinguish red from green

D. he can't distinguish red from green

Diamonds sparkle in many colors because A. light travels very slowly B. light travels very fast C. there is color-dependent absorption D. light velocity depends on color

D. light velocity depends on color

Stealth bombers are undetected by radar, in part because A. of their low heat emission B. of their high speed C. they are made of translucent material D. of the absence of corner reflectors

D. of the absence of corner reflectors

Stress in plastic can be detected by looking at A. the transmission of different colors B. the reflection of different colors C. interference D. polarized light (crossed polaroids)

D. polarized light (cross polaroids)

A stop sign is bright when you shine the headlamps of your car on it. It most likely is covered with A. fluorescent paint B. phosphorescent paint C. tritium D. small glass spheres

D. small glass spheres

Shannon is famous for having invented or discovered (among other things) A. GPS B. Global Hawk C. the sound channel D. the bit

D. the bit

Red-eye demonstrates that A. light is a wave B. air absorbs blue more than red C. camera film is sensitive to red D. the eye is a retroreflector

D. the eye is a retroreflector

A computer screen does not have spots that are colored A. red B. green C. blue D. white

D. white

The colors of an oil slick indicates that A. light is a wave B. light bends when entering material c. light changes its wavelength when passing through oil D. oil is made of many different chemicals with different colors

A. light is a wave

Present-day 3-D movies make use of which technology? A. polarizers B. holograms C. dispersion D. mirages

A. polarizers

Which of the following are retroreflections? Choose all that apply. A. bicycle reflectors B. human eyes C. stop signs D. animal eyes

A. bicycle reflectors B. human eyes C. stop signs D. animal eyes

Which of the following is polarized? A. blue sky light B. direct sunlight (yellow) C. light from a candle D. light from a TV screen

A. blue sky light

A major use of fiber optics is for A. communication B. making flashlights brighter C. focusing light for lasers D. traffic lights

A. communication

A fiber can send much more information per second that a wire because A. light has a very high frequency B. electricity travels better in glass than in wire C. sound travels very rapidly in glass D. light travels faster than electricity

A. light has a very high frequency