Optics - 5 Steps to a 5 500 AP Physics Questions to Know by Test Day

5 Steps to a 5 500 AP Physics Questions to Know by Test Day (2012)

Chapter 16. Optics

451. When a beam of light is refracted through a prism, the beam is spread into what colors?

(A) Violet, blue, green, yellow, orange, and red

(B) Blue, violet, green, yellow, red, and orange

(D) Red, orange, yellow, green, blue, and violet

(E) Orange, red, yellow, green, blue, and violet

452. Why does a piece of glass disappear when immersed in a liquid with the same index of refraction?

(A) The liquid would be dark, and the glass could not be seen.

(B) The liquid and the glass would be the same color.

(D) The glass would be seen at a certain angle.

(E) The liquid causes the glass to melt.

453. What is the focal point of a concave mirror with a radius of 100 cm?

(A) 50 cm

(B) 200 cm

(D) 1 m

(E) 0.5 mm

454. Historians have recorded that Archimedes used mirrors or lenses to burn the Spartan fleet. If he had used mirrors, what would be the focal length of the mirrors Archimedes used to burn the Spartan ships 2 km at sea? Could these be easily made?

(A) 1 km, no

(B) 1 km, yes

(D) 4 km, yes

(E) 4 m, yes

455. If a person were nearsighted, what shape lens would correct the person’s vision?

(A) Concave-convex

(B) Convex-convex

(D) Convex-concave

(E) Flat-convex

456. To correct for chromatic aberration, what type of lens should be used?

(A) Convex-concave

(B) Two lenses of different refraction

(D) A convex-convex lens mated with a concave-concave lens

(E) Concave-convex

457. In a specular reflection, if the incident light beam hits the surface at 45° to normal, at what angle will the reflected beam come from the surface?

(A) 90°

(B) 30°

(D) 45°

(E) 60°

458. Why is it safer to use matte surfaces on surgical instruments rather than polished surfaces during laser surgery?

(A) A matte surface is easier to clean.

(B) A polished surface is easier to clean.

(D) A matte surface would diffuse the laser beam.

(E) Laser-safe eyewear should be worn during surgery.

459. An archerfish spits a stream of water at insects above the water surface to knock them down and eat them. If the fish sees an insect at θ degrees under water, how should the fish aim its spit stream to hit the insect?

(A) Much less than θ degrees

(B) Much greater than θ degrees

(D) Slightly less than θ degrees

(E) At θ degrees

460. To keep as much of the laser beam energy inside a laser fiber, a coating is sometimes placed on the fiber to produce total reflection in the fiber. What refractive index should the coating have?

(A) It should be opaque.

(B) It should be mirrored.

(D) It should be lower than that of the fiber.

(E) It should have a critical angle of greater than 41°.

461. A totally reflecting prism can be used to do what to a beam of light?

(A) Reflect the beam 90°

(B) Reflect the beam 180°

(D) All of the above

(E) Only (A) and (B)

462. Galileo made a telescope to study the heavens. The telescope has a 37-mm diameter plano-convex objective lens with a focal length of 980 mm. According to Galileo’s writings, the original eyepiece, which was lost, was a plano-concave lens with a diameter of approximately 22 mm and a focal length of approximately 50 mm. What was its magnification and how did the image appear?

(A) 26.5, upright

(B) 1.7, inverted

(D) 1.7, upright

(E) 19.6, upright

463. Newton’s telescope was a reflecting telescope with a spherical mirror and a spherical eyepiece lens. Why was it better than Galileo’s telescope?

(A) It eliminated chromatic aberration.

(B) It eliminated spherical aberration.

(D) Only (A) and (B).

(E) Only (A) and (C).

464. The Hubble Space Telescope is a reflecting telescope. Why was it placed in space?

(A) Because of its size

(B) Because of its focal length

(D) Because of the lack of atmospheric aberration

(E) Because of its expense

465. The Cerro Paranal telescope array in southern Chile uses four 8.2-m diameter reflecting telescopes. The site is in the Andes Mountains at 2,600 m above sea level. It is approximately 120 km from the nearest town of any significant size. Why is this a good site for a light telescope? Why isn’t it?

(A) Light pollution is low, but you can only view the Southern Hemisphere.

(B) There is plenty of room on the mountains, but it is not easily accessible for most astronomers.

(D) It is above most of the atmosphere and has low light pollution, but you can only view the Southern Hemisphere.

(E) It is above most of the atmosphere and has low light pollution, but it is affected by the nearby ocean’s humidity.

466. Which color is refracted most when shone on water?

(A) Red

(B) Yellow

(D) Green

(E) Violet

467. If you stand centered between two mirrors that are 2 m apart, how far away will your image appear in the mirror? How many images will you see?

(A) 1 m, an infinity

(B) 2 m, very many

(D) 1 m, very many

(E) 2 m, one

468. A spherical concave mirror has a focal length of 200 cm. If it is used for stargazing, how far from the mirror will the star images appear?

(A) 400 cm

(B) 200 cm

(D) 201 cm

(E) 401 cm

469. What kind of lens should be used to correct eyes with presbyopia (i.e., a condition in which the lens of the eye is unable to focus)?

(A) Concave-convex

(B) Convex-convex

(D) Convex-concave

(E) Flat-convex

470. A person with astigmatism has an eye lens that is not spherical. How can this be corrected?

(A) With a concave-convex lens

(B) With a convex-convex lens

(D) With a convex-concave lens

(E) With a cylindrical lens

471. How does a “one-way” mirror work?

(A) It has a large index of refraction.

(B) It is partially silvered on one side.

(D) One side is darkened.

(E) All of the above.

472. After watering a plant, brown spots may sometimes appear on its leaves. Why?

(A) Acid rain

(B) Insects attracted to the water burrow into the leaf

(D) Dust in the water blocks the sun and the area under the drop dies

(E) The leaf cannot breathe, and the area under the drop dies

473. Why do a cat’s eyes glow in the dark?

(A) A layer of phosphorescent material lines the cat’s retinas

(B) A cat’s eyes are mirrored

(D) A cat’s eyes are prismatic

(E) All of the above, except (C)

474. A person looks over the rim of an empty cylindrical cup and sees the far edge of the bottom. While doing this, the person’s line of sight forms an angle, α, with the side of the cup. When the cup is filled with water, the person can see the center of the cup from the same angle. If the cup is 6 cm in diameter, how deep is the cup? (The index of refraction for water is 1.333 and 1.000 for air.)

475. A convex-convex lens has a focal length of 20 cm. Determine the image distances when an object is placed at 60 cm, 40 cm, 20cm, 10 cm, and 5 cm from the lens.