Download Use the following to answer question 1: A power plant produces a

Use the following to answer question 1:
A power plant produces a voltage of 6.0 kV and 150 A. The voltage is stepped up to
240 kV by a transformer before it is transmitted to a substation. The resistance of the
transmission line between the power plant and the substation is 75 Ω.
1. What percentage of the power produced at the power plant is lost in transmission to the
substation?
A) 0.47 %
B) 0.41 %
C) 0.34 %
D) 0.23 %
E) 0.12 %
2.
A)
B)
C)
D)
E)
The electric field at point A is zero. What is charge Q1?
+32 µC
–32 µC
The field cannot be zero at A for any value of Q1.
+16 µC
–16 µC
3. A 315-Ω resistor is connected in series with a parallel-plate capacitor across the
terminals of a 60.0-Hz ac generator. When the gap between the plates is empty, its
capacitance is 2.65 µF. Determine the ratio of the rms current in the circuit when the
capacitor is empty to that when ruby mica (κ = 5.40) is inserted between the plates?
A) 2.87
B) 2.32
C) 0.430
D) 0.348
E) 0.253
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4. What is the radius of the orbit of an electron moving with a speed of 108 m/s
perpendicular to a magnetic field of 5.0 × 10–3 T ? (Neglect relativistic effects.)
A) 1.1 m
B) 0.11 m
C) 0.34 m
D) 0.011 m
E) 8.9 m
5. The ratio of the abundance of carbon-14 to carbon-12 in a sample of dead wood is one
quarter the ratio for living wood. If the half-life of carbon-14 is 5730 years, how many
years ago did the wood die?
A) 11,460
B) 22,920
C) 4,297.5
D) 2865
E) 1432.5
6.
A)
B)
C)
D)
E)
Which one of the following is a consequence of the postulates of special relativity?
There is no such thing as an inertial reference frame.
Newton's laws of motion apply in every reference frame.
Coulomb's law of electrostatics applies in any reference frame.
The question of whether an object is at rest in the universe is meaningless.
The value of every physical quantity depends on the reference frame in which it is
measured.
7. A uniform electric field of 8 V/m exists between the plates of a parallel plate capacitor.
How much work is required to move a +20 µC point charge from the negative plate to
the positive plate if the plate separation is 0.050 m?
A) 0.4 J
B) 1.6 J
C) 8 × 10−4 J
D) 8 × 10−5 J
E) 8 × 10−6 J
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8. A lens that has an index of refraction of 1.61 is coated with a non-reflective coating
which has an index of refraction of 1.45. Determine the minimum thickness for the film
if it is to be non-reflecting for light of wavelength 560 nm.
A) 1.93 × 10−7 m
B) 3.86 × 10−7 m
C) 4.83 × 10−8 m
D) 9.66 × 10−8 m
E) 8.69 × 10−8 m
9. A 20-µF capacitor is charged to 200 V and is then connected across a 1000-Ω resistor.
The amount of charge on the capacitor after 10 ms is approximately
A) 14 mC
B) 2.4 mC
C) 0.80 mC
D) 1.6 mC
E) 3.2 mC
10. An LR circuit has a resistance R = 25 Ω, an inductance L = 5.4 mH, and a battery of emf
= 9.0 V. How much energy is stored in the inductance of this circuit when a steady
current is achieved?
A) zero
B) 0.35 J
C) 0.35 mJ
D) 0.70 mJ
E) 0.97 mJ
11. A person standing 2.0 m away from a convex mirror and notices that their image height
is 1/4 of their actual height. Determine the radius of curvature of the mirror.
A) 0.67 m
B) 1.33 m
C) 2.0 m
D) 4.0 m
E) 6.0 m
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12. An incandescent light bulb radiates uniformly in all directions with a total average
power of 1.0 × 102 W. What is the maximum value of the magnetic field at a distance
of 0.50 m from the bulb?
A) 8.4 × 10−7 T
B) 5.2 × 10−7 T
C) 3.1 × 10−7 T
D) 1.6 × 10−7 T
E) zero tesla
Use the following to answer question 13:
An object is placed 20 cm from a converging lens with focal length 15 cm. A concave
mirror with focal length 10 cm is located 75 cm to the right of the lens as shown in the
figure. Note: The figure is not drawn to scale.
13.
A)
B)
C)
D)
E)
Determine the location of the final image.
48 cm to the right of the lens
96 cm to the right of the lens
30 cm to the left of the mirror
0.225 cm to the left of the mirror
0.225 cm to the right of the mirror
14. A charged particle is fired from a gun with a velocity of 5.2 × 104 m/s at an angle of 35°
with respect to a 0.0045-T magnetic field. If the magnetic field exerts a force of 0.0026
N on the particle, determine the magnitude of the charge.
A) 11 µC
B) 15 µC
C) 19 µC
D) 23 µC
E) 27 µC
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Use the following to answer question 15:
Five resistors are connected as shown in the diagram. The potential difference between
points A and B is 15 V.
15.
A)
B)
C)
D)
E)
What is the current in the 3.6-Ω resistor?
1.3 A
1.7 A
2.9 A
3.5 A
15 A
16. You connect two capacitors C1 = 15 pF and C2 = 30 pF in series across a 1.5-V battery.
The potential difference across capacitor C1 is approximately
A) 0.50 V
B) 1.0 V
C) 1.5 V
D) 0.33 V
E) 0.67 V
17. An astronomer observes electromagnetic waves emitted by oxygen atoms in a distant
galaxy that have a frequency of 5.710 × 1014 Hz. In the laboratory on earth, oxygen
atoms emit waves that have a frequency of 5.841 × 1014 Hz. Determine the relative
velocity of the galaxy with respect to the astronomer in earth.
A) 6.724 × 106 m/s, away from earth
B) 6.724 × 106 m/s, toward earth
C) 2.931 × 108 m/s, away from earth
D) 4.369 × 104 m/s, toward earth
E) 4.369 × 104 m/s, away from earth
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18. A laser emits a single, 2.0-ms pulse of light that has a frequency of 2.83 × 1011 Hz and a
total power of 75 000 W. How many photons are in the pulse?
A) 8.0 × 1023
B) 1.6 × 1024
C) 2.4 × 1025
D) 3.2 × 1025
E) 4.0 × 1026
19. Two electrons are ejected in opposite directions from atoms in a sample of radioactive
material. Each electron has a speed, as measured by a laboratory observer, of 0.6c.
What is the speed of one electron as seen from the other electron?
A) 0.361c
B) 0.882c
C) 1.87c
D) zero
E) 1.24c
20. A battery is used to charge a parallel-plate capacitor, after which it is disconnected.
Then the plates are pulled apart to twice their original separation. This process will
double the:
A) capacitance
B) surface charge density on each plate
C) stored energy
D) electric field between the two places
E) charge on each plate
21. An electron is released from rest in a uniform electric field of 1.25 kN/C. What is the
electron's velocity after 20 x10-9 s? (Neglect relativistic effects.)
A) 2.5 × 10–5 m/s
B) 3.9 × 103 m/s
C) 3.0 × 108 m/s
D) 2.5 × 103 m/s
E) 4.4 × 106 m/s
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Use the following to answer question 22:
Two long, straight wires separated by 0.10 m carry currents of 18 A and 6 A in the same
direction as shown.
22.
A)
B)
C)
D)
E)
Determine the magnitude of the magnetic field at the point P.
2.4 × 10−5 T
4.8 × 10−5 T
7.2 × 10−5 T
9.6 × 10−5 T
zero tesla
23. A large, flat conducting plate, 20m on a side, has a surface charge density σ = 8.0 × 10–9
C/m2 on one of its surfaces. What is the magnitude of the electric field 10 µm from this
plate?
A) 72 N/C
B) 0.23 kN/C
C) 0.90 kN/C
D) 90 MN/C
E) 9.0 × 1012 N/C
24. A single, whole-body dose of 450 rem is considered a lethal dose for approximately
fifty percent of all individuals receiving such a dose. If a 62-kg person were exposed to
such a dose of radiation that has an RBE of 0.845, how much energy has the person
absorbed?
A) 480 J
B) 5.3 J
C) 75 J
D) 120 J
E) 330 J
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Use the following to answer question 25:
A loop is pulled with a force F to the right to maintain a constant speed of 8.0 m/s. The
loop has a length of 0.15 m, a width of 0.08 m, and a resistance of 200.0 Ω. At the
instant shown, the loop is partially in and partially out of a uniform magnetic field that
is directed into the paper. The magnitude of the field is 1.2 T.
25.
A)
B)
C)
D)
E)
Determine the magnitude of the force F required to pull the loop.
1.3 × 10−4 N
2.1 × 10−4 N
3.7 × 10−4 N
6.8 × 10−4 N
9.0 × 10−4 N
26. An FM radio station emits an electromagnetic wave which is received by a circuit
containing a 3.33 × 10−7 H inductor and a variable capacitor set at 7.31 × 10−12 F. What
is the frequency of the radio wave?
A) 1.02 × 108 Hz
B) 8.80 × 107 Hz
C) 1.58 × 108 Hz
D) 9.40 × 107 Hz
E) 9.80 × 107 Hz
27. A solid spherical conductor of radius 20 cm has a charge Q = 25 nC on it. A second,
initially uncharged, spherical conductor of radius 12 cm is moved toward the first until
they touch and is then moved far away from it. How much charge is there on the second
sphere after the two spheres have been separated?
A) 15 nC
B) 9.4 nC
C) 25 nC
D) 3.9 nC
E) 2.1 nC
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28. A beryllium nucleus (Z = 4) has a single electron bound to it in the n=2 state. Determine
the energy of the photon that can be emitted if the electron changes state.
A) 13.6 eV
B) 54.4 eV
C) 122 eV
D) 163 eV
E) 218 eV
Use the following to answer question 29:
A 0.10-m long solenoid has a radius of 0.05 m and 1.5 × 104 turns. The current in the
solenoid changes at a rate of 6.0 A/s. A conducting loop of radius 0.02 m is placed at
the center of the solenoid with its axis the same as that of the solenoid as shown.
29.
A)
B)
C)
D)
E)
Determine the induced emf in the loop.
0.7 × 10−3 V
1.4 × 10−3 V
2.8 × 10−3 V
5.6 × 10−3 V
zero volts
30. You have three sockets in your kitchen that are wired into the same circuit that has a 25
Amp circuit breaker. Assume the sockets provide 120 V RMS voltage. You have the
following appliances in your kitchen, each of which hasa different effective resistance
when in operation: blender (30 Ohm), refrigerator (18 Ohm), microwave oven (12
Ohm), toaster (9 Ohm), and dishwasher (7 Ohm). Which of the following combinations
of appliances is it safe to plug in and run without tripping the circuit breaker?
A) dishwasher and blender
B) blender, refrigerator and microwave oven
C) toaster and microwave oven
D) microwave oven and refrigerator
E) dishwasher and toaster
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Answer Key
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
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22.
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24.
25.
26.
27.
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29.
30.
E
A
D
B
A
D
E
D
B
C
B
B
C
C
B
B
A
A
B
C
E
B
C
E
C
A
B
D
B
D
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