Name: ________________________ Class: ___________________ Date: __________
AP Physics 2 - Geometric Optics Practice Test (Multiple Choice Section) Directions: Mark only one answer for each question. Use g = 10 m/s2 for simplicity. 1.
A box with holes in opposite sides contains an optical element. A real inverted image is formed at I of an object placed at O as shown. The optical element contained in the box is a
a. b.
Diverging lens Converging lens
c. d.
Diverging (convex) mirror Converging (concave) mirror
2.
A converging lens is set with its vertex at V. Points F and F ' represent lens's focal points; points A and A ' are both two focal lengths away from the lens. An object is placed upright on the lens's axis at a position between A and F. Where is the image located?
a. b.
At point A ' Beyond point A '
c. d.
Between the lens and F ' Between F ' and A '
3.
A concave mirror is set with its vertex at V. Points F and C represent the mirror's focal point and curvature center, respectively. An object is placed upright on the mirror's axis between F and the mirror. Which of the following describes the orientation of the image and its size relative to the object? a. b.
Inverted and smaller Upright and smaller
c. d.
Inverted and larger Upright and larger
3 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
4.
The diagram shows a region of space where a plane mirror is set perpendicular to the plane of the page. A light source is placed at point P, and two rays emitted by the source are drawn. The reflections of the rays are also shown. Which of the numbered points represents the image of point P?
a.
Point 1
b.
Point 2
c.
Point 3
d.
Point 4
e.
Point 5
5.
A student performs an experiment in order to determine the focal length of a converging lens. The student uses the magnifying glass to focus the real image of a candle onto an index card. The student varies the distance between the magnifying glass and the candle, so, and measures the distance to the focused image, si. The student then plots a graph of the reciprocal distances 1/so and 1/sias shown. If the student is working in units of meters, what is the focal length of the lens? a.
0.2 m
b.
0.4 m
c.
1m
d.
2.5 m
e.
5m
2 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
6. An upright object is placed in front of a diverging lens. The object could be placed either closer to the
lens than the focal point or farther from the lens than the focal point. All of the following diagrams show a correct principal ray drawn from the object through the lens EXCEPT
a.
c.
b.
d.
Questions 7-8: A candle can be placed in front of a lens or mirror as shown in the diagrams below.
(A)
(B)
(D)
(E)
(C)
7. In which case can the image of the candle be projected onto a card? a.
A
b.
B
c.
C
d.
D
e.
E
8. In which case is the candle’s image smaller than and on the same side of the lens/mirror as the object? a.
A
b.
B
c.
C
d.
D
e.
E
3 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
9. An object, which could be upright or inverted, is placed in front of a convex mirror. All of the following
diagrams show a correct principal ray drawn from the object and reflected from the mirror EXCEPT
a.
c.
b.
d.
10. At what minimum angle to the normal will a light ray entering a medium with an index of refraction of
n = 1.6 from a medium with an index of refraction of n = 2.0 experience total internal reflection? a.
37o
b.
30o
c.
45o
d.
53o
e.
60o
11.
A ray of light passes through a piece of glass at the angle of incidence shown. As the light passes through the glass and exits the glass into the air, the path of the ray is represented by which of the rays shown?
a.
A
b.
B
c.
C
d.
D
e.
E
4 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
12.
Students in a lab group are given a plastic block with a hollow space in the middle, as shown in the figures. The index of refraction nP of the plastic is known. The hollow space is filled with a gas, and the students are asked to collect the data needed to find the index of refraction nG of the gas. The arrow represents a light beam that they shine into the plastic. They take the following set of measurements: Angle of incidence of the light in the air above the plastic block = 30° Angle of refraction of the beam as it enters the plastic from the air = 45° Angle of refraction of the beam as it enters the plastic from the gas = 45° The three measurements are shared with a second lab group. Can the second group determine a value of nG from only this data? a. b. c. d.
Yes, because they have information about the beam in air and in the plastic above the gas. Yes, because they have information about the beam on both sides of the gas. No, because they need additional information to determine the angle of the beam in the gas. No, because they do not have multiple data points to analyze.
13. A converging lens is used to form a real image of an object placed outside the focal point of the lens.
Which of the following would increase the size of the real image? a. b. c. d. e.
Moving the object closer to the lens but keeping it outside the focal point Moving the object to a position inside the focal point Moving the lens farther from the object Replacing the lens with one in the same position with the same focal length but a greater diameter Replacing the lens with one in the same position with the same diameter but a smaller focal length
5 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
14.
A laser beam is directed at the surface of a smooth, calm pond as represented in the diagram. Which organisms could be illuminated by the laser light?
a. b. c.
The bird and the fish The bird and the seaweed The crab and the seaweed
d. e.
The crab and the fish The seaweed only
Questions 15-16: A student performs an experiment to determine the focal length of a simple magnifier. Using a centimeter scale, the student positions a lit candle at 17 cm, the magnifier at 13 cm, and a screen at 1 cm as shown above. In these positions, a real image of the candle appears on the screen. 15. What is the focal length of the magnifier? a.
1 cm
b.
3 cm
c.
4 cm
d.
8 cm
e.
12 cm
16. Without moving the screen or candle, there is a second location where the magnifier can be placed so that
a new real image is formed on the screen. At what position must the magnifier be placed to form this new image, and how large is the new image compared to the candle? New Magnifier Position a. 4 cm b. 5 cm c. 5 cm d. 9 cm e. 14 cm
New Image Size Larger than the candle Smaller than the candle Larger than the candle Larger than the candle Smaller than the candle
6 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
17. When one uses a magnifying glass to read fine print, one uses a a. b. c. d.
converging lens to produce a virtual image of the print converging lens to produce a real image of the print diverging lens to produce a virtual image of the print diverging lens to produce a real image of the print
18. A large lens is used to focus an image of an object onto a screen. If the left half of the lens is covered
with a dark card, which of the following occurs? a. b. c. d.
The left half of the image disappears. The right half of the image disappears. The image becomes blurred. The image becomes dimmer.
Directions: Mark two answers for each question. 19. The following diagrams show a light ray from an object at O that passes through a lens having focal
points F. Assume that the thin lens approximation is used in drawing the diagrams. Which diagrams show a converging lens? Select two answers.
(A)
(B)
(C)
(D)
7 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
20. The image of the arrow is larger than the arrow itself in which of these cases? Select two answers.
8 © 2014 John R. Frensley, The College Entrance Examination Board, et.al. All rights reserved.
