ame: ________________________ Class: ___________________ Date: __________
Exam 1--PHYS 102--S12
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Which of these statements is true about charging by induction?
a.
____
it causes a bigger charge than charge by c. it can not be done to conductors
conduction
b. it does not require contact between two
d. it can only occur with protons
charged objects
2. What is the magnitude of the force acting on the charge q 2?
a.
b.
3.2 N
0.009 N
c.
d.
1
0.018
0N
ID: A
ame: ________________________
____
____
____
ID: A
3. What is the direction of the force acting on q 2?
a. 127º from the +x axis
c. 37º from the +x axis
b. 53º from the +x axis
d. 143º from the +x axis
4. What is the magnitude of the force acting on q 1?
a. 2.2 N
c. 54 N
b. 11 N
d. 7.7 N
5. What is the magnitude of the electric field at the position of q 2?
a. 2.2 N/C
c. 72000 N/C
b. 0.000066 N/C
d. 54 N/C
2
ame: ________________________
____
ID: A
6. Look at this kid. What is her problem?
a.
b.
____
the back of her head is positively charged c. the day is really, really humid
all of the negative charges on her head
d. she has an excess of negative charges in
have moved to the ends of her hair
her hair
7. A charged particle sits in an electric field as shown here. If the particle moves in the direction of dashed line
(to the left), what is the charge of the particle?
a.
b.
positive
negative
c.
d.
3
neutrally charged
You must know the magnitude of the
E-field to know the sign of the charge.
ame: ________________________
____
____
ID: A
8. The following figure shows equipotential lines for a configuration of charges. Which charge has the greater
magnitude?
a. the negative charge
c. both have the same magnitude
b. the positive charge
d. there is not enough information
9. The following is a plot of potential (V) versus position (x). You release a proton at the point x=A. What will
the particle do?
a.
b.
go to the right
remain stationary
c.
d.
4
oscillate back and forth
go to the left
ame: ________________________
ID: A
____ 10. What is the equivalent capacitance of this circuit?
a. 0.6 µF
c. 5 µF
d. 0.5 µF
b. 12 µF
____ 11. In the previous question, what is the voltage across C 2, the 6 µF capacitor?
a. 8 V
c. 4 V
b. 12 V
d. 6 V
____ 12. In the previous circuit, what is the charge across C 4, the 2 µF capacitor?
a. 24 µC
c. 6 µC
d. 12 µC
b. 0.2 µC
5
ame: ________________________
ID: A
____ 13. What is the potential and electric field at the point P, which is in the center of this square?
a. E≠0, V≠0
c.
b. E≠0, V=0
d.
____ 14. What is the voltage across C 1, the 2 µF capacitor?
E=0, V≠0
E=0, V=0
a. 6 V
c. 12 V
b. 4 V
d. 3 V
____ 15. You charge a capacitor with a battery of 10 V. Then you remove the battery, so the charge remains constant.
Then you double the distance between the plates of the capacitor. What is the new voltage across the
capacitor?
a.
b.
5V
20 V
c.
d.
6
100 V
10 V
ame: ________________________
ID: A
____ 16. What is the primary purpose of a capacitor?
a. to create a current
c. to complete a circuit
b. to create a potential difference
d. to store electrical energy
____ 17. What is the potential at the cross marked with the letter P?
a. 4 V
c. -1 V
b. 18 V
d. 0 V
____ 18. For the previous question, how much work is required to assemble the 2 charges?
c. -6×10-8J
a. 4×103J
b. 3 J
d. -2×10-8J
____ 19. You wish to measure the potential difference across a resistor. How do you hook up the device?
a.
in parallel with the resistor
c.
you can’t measure the potential
difference across a resistor.
b. replace the resistor with the device
d. in series with the resistor
____ 20. Your hair dryer has a power of 1000 W. If it operates at a voltage of 120 V, how much charge passes
through the wire in 1 minute?
a.
b.
8.3 C
120,000 C
c.
d.
7
7.2 C
500 C
ame: ________________________
ID: A
____ 21. Which has a bigger resistance, a hair dryer (1000 W) or a light bulb (100 W)?
a. both the same
c. hair dryer
b. light bulb
d. not enough info to tell
____ 22. Consider this circuit. What is the current through the resistor?
a. 48 A
c. 0.16 A
b. 0.08 A
d. 12 A
____ 23. The rate for electricity charged by Entergy is $0.05 per kilowatt-hour. How much does it cost you to run
your 1000 W electric heater for 2 hours?
a. $0.40
b. $100
____ 24. Which of these best describes an ammeter?
c.
d.
$4
$0.10
a. it has a very high power rating
b. it is hooked up in parallel with a resistor
____ 25. This is version A. Bubble A for this question.
a. A
b. B
c.
d.
it measures voltage
it has a very small resistance
c.
d.
C
D
8
ID: A
Exam 1--PHYS 102--S12
Answer Section
MULTIPLE CHOICE
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