Download Exam 3--PHYS 102--S14

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Exam 3--PHYS 102--S14
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1. Which of these statements is always true?
a. resistors in parallel have the same voltage
b. the equivalent resistance of resistors in parallel
is bigger than any one of the resistors
c. the sum of the potentials for resistors in series
is zero
d. the current for resistors in parallel is the same
5. For the previous circuit, what is the current through
the 6 resistor?
a. 3 A
b. 12 A
c. 2 A
d. 1 A
e. 0.5 A
2. The terminal voltage of a battery is always
____________ than the ideal electromotive force
because of _______________.
a. smaller, Ohm’s law
b. larger, large current
c. smaller, internal resistance
d. larger, 
6. An ohm is a unit of
a. resistivity
b. inductance
c. potential difference
d. resistance
e. current
7. Consider this circuit. If one of the 2  resistors is
removed, what happens to the voltage across the
remaining resistor?
3. What is the equivalent resistance of this circuit?
a.
b.
c.
d.
a.
b.
c.
d.
11 
1.6 
1
4
it increases
it is the same
it decreases
it depends on how quickly you remove the
resistor
8. For the above circuit, what happens to the total
current coming off of the battery if you remove one
of the resistors?
a. it increases
b. it remains the same
c. it decreases
4. For the previous problem, what is the voltage
across the 2 resistor?
a. 3 V
b. 4 V
c. 6 V
d. 8 V
e. 12 V
1
9. Consider this circuit. What is the equivalent
resistance?
13. The third prong in the electrical outlet provides
protection from _______________.
a. very wet areas
b. faulty devices
c. too much current on a circuit
d. your gossipy aunt
14. Consider a series RC circuit for which R = 2.0 M,
C=5.0 µF, and =20 V. Find the charge on the
capacitor 10 s after the switch is closed.
a.
b.
c.
d.
e.
10 
1.7 
7
0.4 
1.2 
a.
b.
c.
d.
e.
10. Consider the circuit in the previous problem. For
which resistor is the current greatest?
a. R1
b. R2
c. R3
d. R5
52 F
63 F
100 F
37 F
200 F
15. Which of the following equations for this circuit is
correct?
11. Consider this circuit. Which of the following
graphs represents the current versus time after the
switch is closed and current is allowed to flow in
the circuit.
a.
b.
c.
d.
a.
b.
c.
d.
A
B
C
D
-6I2+10+4I1+14=0
-6+10+6I2=0
14-4I3+6=0
14-4I1+6I3=0
16. Consider the above circuit. What is magnitude and
direction of I2?
12. A 4.0  resistor, an 8.0  resistor, and a 12 
resistor are connected in series with a 12 V battery.
What is the current in the 8.0  resistor?
a.
b.
c.
d.
a.
b.
c.
d.
0.25 A
0.5 A
2.0 A
1.0 A
2
0A
1.5 A to the left
0.67 A to the right
2.7 A to the right
17. If the switch S is closed, what happens to the
current through R1?
20. Which of these statements about a household
circuit is true:
I. The household circuit is a series circuit.
II. All devices in a household circuit operate at the
same current.
III. As you add more devices to a household circuit,
the total current increases.
a.
b.
c.
d.
IV. A ground fault circuit interrupt turns off if
Iin>Iout for any particular device.
decreases
stays the same
increases
not enough information
a.
b.
c.
d.
18. You turn on a light in your house. What happens
to the potential across other applicances on the
same circuit?
a.
b.
c.
II & III
III
III & IV
I & IV
21. A capacitor is allowed to fully discharge. Which of
these graphs represents the voltage versus time for
that capacitor?
the potential increases
the potential decreases
the potential stays the same
19. Consider these wires with the currents as labeled.
What is the magnitude and direction of I?
`
a.
b.
c.
d.
a.
b.
c.
d.
20 A to the left
35 A to the right
10 A to the left
25 A to the right
A
B
C
D
22. A battery has an internal resistance of 2 . Its
ideal electromotive force is 20 V. If the current
coming off of the battery is 5 A, what is the
terminal voltage of the battery?
a. 10 V
b. 15 V
c. 20 V
d. 30 V
e. 35 V
3
23. Consider this circuit. Which of the equations is a
correct use of the loop rule?
a.
b.
c.
d.
26. For the previous circuit, which resistor has the
larger voltage?
a. 1 
b. top 2 
c. bottom 2 
d. either the top or bottom 2 
e. all have the same voltage
-I1R1-I4R4-V=0
V-I1R1-I2R2-I3R3=0
+I3R3-I2R2=0
+I2R2-I1R1-V=0
24. Consider this circuit. What is the current through
the 10  resistor?
a.
b.
c.
d.
10 A
2A
5A
1A
25. Consider this circuit. What happens to the total
current if you remove the 1  resistor?
a.
b.
c.
d.
Total current increases
Total current decreases
Total current is the same
Total current is zero
4
ID: A
Exam 3--PHYS 102--S14
Answer Section
MULTIPLE CHOICE
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