|
|
81. Two hollow-core solenoids, A and B, are connected by a wire, as shown in the
diagram below. Two bar magnets, 1 and 2, are suspended just above the solenoids.
If the north pole of magnet 1 is dropped through solenoid A, the south pole of magnet
2 will simultaneously be
- attracted by a magnetic force toward solenoid B
- repelled by a magnetic force away from solenoid B
- repelled by an electric force away from solenoid B
- unaffected by solenoid B
|
|
|
82. Which device can be used to increase the voltage from a source of direct current?
- electroscope
- mass spectrometer
- induction coil
- generator
|
|
|
83. The graph below shows induced potential difference versus time for the rotating
armature of a generator.
What is the frequency of armature rotation?
- 10 Hz
- 20 Hz
- 40 Hz
- 60 Hz
|
|
|
84. The transformer on a power pole steps down the voltage from 10,800 volts to
120. volts. If the secondary coil contains 360 turns, how many turns are on the
primary?
- 30
- 90
- 3600
- 32,400
|
|
|
Note that question 85 has only three choices.
85. An electron is located between a pair of oppositely charged plates. As the electron
approaches the positive plate, the kinetic energy of the electron
- decreases
- increases
- remains the same
|
 |
|
|
86. In the diagram below, a source produces a light that is reflected from a plane
mirror.
To an observer at point O, the light appears to originate from point
- A
- B
- C
- D
|
|
|
87. A spherical mirror that forms only virtual images has a radius of curvature
of 0.50 meter. The focal length of this mirror is
- -0.25 m
- +0.25 m
- -0.50 m
- +0.50 m
|
|
|
88. A spherical concave mirror is used in the back of a car headlight. Where must
the bulb of the headlight be located to produce a parallel beam of reflected light?
- between the principal focus and the mirror
- beyond the center of curvature of the mirror
- at the principal focus of the mirror
- at the center of curvature of the mirror
|
|
Base your answers to questions 89 through 91 on the information and diagram below.
An object is located at the center of curvature C of a concave spherical mirror
with principal focus F. The focal length of the mirror is 0.10 meter.
|
|
|
89. At what distance from the mirror is the image located?
- 0.10 m
- 0.20 m
- 0.30 m
- 0.40 m
|
|
|
90. At what distance from the mirror could the object be placed to produce a virtual
image of the object?
- 0.05 m
- 0.10 m
- 0.30 m
- 0.50 m
|
|
|
Note that question 91 has only three choices.
91. As the object is moved from point C toward point F, the size of the image
- decreases
- increases
- remains the same
|
Base your answers to questions 92 and 93 on the information below.
A crown glass converging lens has a focal length of 0.10 meter.
|
|
|
92. Which cross-sectional diagram best represents this lens?
|
|
|
93. An object is placed 0.30 meter from the lens. How far from the lens will
an image of the object be formed?
- 0.30 m
- 0.20 m
- 0.15 m
- 0.10 m
|
|
|
94. An object 0.080 meter high is placed 0.20 meter from a converging
(convex) lens. If the distance of the image from the lens is 0.40 meter,
the height of the image is
- 0.010 m
- 0.040 m
- 0.080 m
- 0.16 m
|
|
|
95. A diverging (concave) lens can form images that are
- virtual, only
- inverted, only
- either virtual or real
- either inverted or erect
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
|
|
 |
