# ExamView - DC Circuits.tst - Ccphysics.us

Electronics - Devices

Oct 7, 2013 (4 years and 7 months ago)

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1
DC Circuits
____ 1. The two ends of a 3.0- resistor are connected to a 9.0-V battery. What is the current through the resistor?
a.27 A c.3.0 A
b.6.3 A d.0.33 A
____ 2. The two ends of a 3.0- resistor are connected to a 9.0-V battery. What is the total power delivered by the
battery to the circuit?
a.3.0 W c.0.33 W
b.27 W d.0.11 W
____ 3. Three 8.0- resistors are connected in series. What is their equivalent resistance?
a.24.0  c.0.38

1
, I
2
and I
3
. Which of the following expresses
the value of the total current I
T
in the system made up of the three resistors in series?
a.I
T
= I
1
+ I
2
+ I
3
c.I
T
= I
1
= I
2
= I
3
b.I
T
= (1/I
1
+ 1/I
2
+ 1/I
3
) d.I
T
= (1/I
1
+ 1/I
2
+ 1/I
3
)

1

1
, V
2
and V
3
, respectively. Which of
the following expresses the value of the total voltage V
T
taken over the three resistors together?
a.V
T
= V
1
+ V
2
+ V
3
c.

V
T
=

V
1
=

V
2
=

V
3
b.V
T
= (1/V
1
+ 1/V
2
+ 1/V
3
) d.

V
T
= (1/

V
1
+ 1/

V
2
+ 1/V
3
)

1
____ 6. Three resistors with values of R
1
, R
2
and R
3
, respectively, are connected in series. Which of the following
expresses the total resistance, R
T
, of the three resistors?
a.R
T
= R
1
+ R
2
+ R
3
c.R
T
= R
1
= R
2
= R
3
b.R
T
= (1/R
1
+ 1/R
2
+ 1/R
3
) d.R
T
= (1/R
1
+ 1/R
2
+ 1/R
3
)

1
____ 7. Three resistors, with values of 2.0, 4.0 and 8.0 , respectively, are connected in series. What is the overall
resistance of this combination?
a.0.58  c.7.0 
b.1.1  d.14.0 
____ 8. Three resistors, each with resistance R
1
, are in series in a circuit. They are replaced by one equivalent resistor,
R. Comparing this resistor to the first resistor of the initial circuit, which of the following is true?
a.The current through R equals the current
through R
1
.
c.The power given off by R equals the
power given off by R
1
.
b.The voltage across R equals the voltage
across R
1
.
d.R is less than R
1
.
____ 9. Three resistors connected in parallel each carry currents labeled I
1
, I
2
and I
3
. Which of the following expresses
the value of the total current I
T
in the combined system?
a.I
T
= I
1
+ I
2
+ I
3
c.I
T
= I
1
= I
2
= I
3
b.I
T
= (1/I
1
+ 1/I
2
+ 1/I
3
) d.I
T
= (1/I
1
+ 1/I
2
+ 1/I
3
)

1
2
____ 10. Three resistors connected in parallel have the individual voltages labeled V
1
, V
2
and V
3
, respectively.
Which of the following expresses the total voltage V
T
across the three resistors when connected in this
manner?
a.V
T
= V
1
+ V
2
+ V
3
c.

V
T
=

V
1
=

V
2
=

V
3
b.V
T
= (1/V
1
+ 1/V
2
+ 1/V
3
) d.

V
T
= (1/

V
1
+ 1/

V
2
+ 1/V
3
)

1
____ 11. Three resistors with values R
1
, R
2
and R
3
, respectively, are connected in parallel. Which of the following
expresses the total resistance, R
T
, of the three resistors when connected in parallel?
a.R
T
= R
1
+ R
2
+ R
3
c.R
T
= R
1
= R
2
= R
3
b.R
T
= (1/R
1
+ 1/R
2
+ 1/R
3
) d.R
T
= (1/R
1
+ 1/R
2
+ 1/R
3
)

1
____ 12. Three resistors, each with resistance R
1
, are in parallel in a circuit. They are replaced by one equivalent
resistor, R. Compare this resistor to the first resistor of the initial circuit. Which of the following statements is
true?
a.The current through R equals the current
through R
1
.
c.The power given off by R equals the
power given off by R
1
.
b.The voltage across R equals the voltage
across R
1
.
d.R is greater than R
1
.
____ 13. If R
1
< R
2
< R
3
,

and if these resistors are connected in parallel in a circuit, which one has the highest current?
a.R
1
c.R
3
b.R
2
d.All have the same current.
____ 14. What is Kirchhoff’s 1st equation for this junction?
a.I
1
= I
2
+ I
3
c.I
3
= I
1
+ I
2
b.I
2
= I
1
+ I
2
d.I
1
+ I
2
+ I
3
= 0
____ 15. If I
1
goes to the right through R
1
, I
2
goes to the right through R
2
, and I
3
goes to the right through R
3
, what is
the resulting equation resulting from applying Kirchhoff’s junction rule at point b?
a.I
1
+ I
2
+ I
3
= 0 c.I
1
– I
2
+ I
3
= 0
b.I
1
+ I
2
– I
3
= 0 d.I
1
– I
2
– I
3
= 0
3
____ 16. The internal resistances of an ideal voltmeter and an ideal ammeter are respectively (ideal meaning the
behavior of the system is not changed when using the meter):
a.zero and zero.c.zero and infinite.
b.infinite and infinite.d.infinite and zero.
____ 17. When a 24.0- resistor is connected across a 12.0-V battery, a current of 482 mA flows. What is the internal
resistance of the battery?
a.0.02  c.25.0

output delivered by the emf of the battery?
a.0.21 W c.5.78 W
b.5.57 W d.6.00 W
____ 19. Which resistor is in series with resistor R?
a.R
1
c.R
3
b.R
2
d.R
4
____ 20. If R
1
< R
2
< R
3
,

and if these resistors are connected in series in a circuit, which one dissipates the greatest
power?
a.R
1
c.R
3
b.R
2
d.All are equal in power dissipation.
____ 21. Resistors of values 8.0 , 12.0 , and 24.0  are connected in series across a battery with a small internal
resistance. Which resistor dissipates the greatest power?
a.the 8.0- resistor c.the 24.0-

⁲敳楳瑯

resistance of the battery.
____ 22. Three 8.0- resistors are connected in parallel. What is their equivalent resistance?
a.0.054  c.0.38

resistors?
a.16 A c.3.0 A
b.9.0 A d.48 A
____ 24. Three resistors, with values of 2.0, 4.0 and 8.0 , respectively, are connected in parallel. What is the overall
resistance of this combination?
a.0.58  c.7.0

4
____ 25. Two resistors of values 6.0 and 12.0  are connected in parallel. This combination in turn is hooked in series
with a 4.0- resistor. What is the overall resistance of this combination?
a.0.50  c.8.0 
b.2.0  d.22.0 
____ 26. Two resistors of values 6.0 and 12.0  are connected in parallel. This combination in turn is hooked in series
with a 2.0- resistor and a 24-V battery. What is the current in the 2- resistor?
a.2.0 A c.6.0 A
b.4.0 A d.12 A
____ 27. Two resistors of values 6.0 and 12.0  are connected in parallel. This combination in turn is hooked in series
with a 4.0- resistor and a 24-V battery. What is the current in the 6- resistor?
a.2.0 A c.6.0 A
b.3.0 A d.12 A
____ 28. Which two resistors are in parallel with each other?
a.R and R
4
c.R
2
and R
4
b.R
2
and R
3
d.R and R
1
____ 29. Resistors of values 6.0, 4.0, 10.0 and 7.0 are combined as shown. What is the equivalent resistance for
this combination?
a.2.3  c.10.7 
b.3.0  d.27 
____ 30. What is the equivalent resistance for these 3.00- resistors?
a.1.33  c.3.00

5
____ 31. How much current is flowing in one of the 10- resistors?
a.0.8 A c.1.6 A
b.2.0 A d.2.4 A
____ 32. How much power is being dissipated by one of the 10- resistors?
a.24 W c.16 W
b.9.6 W d.6.4 W
____ 33. If  = 9.0 V, what is the current in the 15- resistor?
a.0.20 A c.0 10 A
b.0.30 A d.0.26 A
____ 34. Consider the circuit shown in the figure. What power is dissipated by the entire circuit?
a.14 W c.52 W
b.28 W d.112 W
6
____ 35. If I
1
goes to the right through R
1
, I
2
goes to the right through R
2
, and I
3
goes to the right through R
3
, what is
the resulting equation resulting from applying Kirchhoff’s loop rule for a clockwise loop around the perimeter
of the circuit?
a.8.0 V + I
1
R
1
+ I
3
R
3
= 0 c.8.0 V – I
1
R
1
+ I
3
R
3
= 0
b.8.0 V + I
1
R
1
– I
3
R
3
= 0 d.–8.0 V + I
1
R
1
+ I
3
R
3
= 0
____ 36. What is the current flowing through the 2- resistor?
a.2 A c.4 A
b.3 A d.6 A
____ 37. What is the current flowing through the 4- resistor?
a.1 A c.3 A
b.2 A d.6 A
____ 38. Four 1.5-volt AA batteries in series power a transistor radio. If the batteries hold a total charge of 240 C, how
long will they last if the radio has a resistance of 200 ?
a.1.1 h c.4.1 h
b.2.2 h d.13 h
7
____ 39. In a circuit, a current of 2.0 A is drawn from a battery. The current then divides and passes through two
resistors in parallel. One of the resistors has a value of 64  and the current through it is 0.40 A. What is the
value of the other resistor?
a.8.0  c.24 
b.16  d.32 
____ 40. A 10-V-emf battery is connected in series with the following: a 2-µF capacitor, a 2- resistor, an ammeter,
and a switch, initially open; a voltmeter is connected in parallel across the capacitor. At the instant the switch
is closed, what are the current and capacitor voltage readings, respectively?
a.zero A, 10 V c.5 A, zero V
b.zero A, zero V d.5 A, 10 V
____ 41. A 10-V-emf battery is connected in series with the following: a 2-F capacitor, a 2- resistor, an ammeter,
and a switch, initially open; a voltmeter is connected in parallel across the capacitor. After the switch has been
closed for a relatively long period (several seconds, say), what are the current and capacitor voltage readings,
respectively?

a.zero A, 10 V c.5 A, zero V
b.zero A, zero V d.5 A, 10 V
____ 42. A circuit contains a 6.0-V battery, a 4.0- resistor, a 0.60-µF capacitor, an ammeter, and a switch all in series.
What will be the current reading immediately after the switch is closed?
a.zero c.1.5 A
b.0.75 A d.10 A
8
____ 43. A circuit contains a 6.0-V battery, a 4.0- resistor, a 0.60-µF capacitor, an ammeter, and a switch in series.
What will be the charge on the capacitor 10 min after the switch is closed?
a.zero c.3.6

C

C d.㈮㐠

C

capacitor is initially uncharged. What is the value of the current the moment after the switch is closed?
a.0.39 A c.0.84 A
b.0.33 A d.2 000 A
____ 45. A 1 000-V battery, a 3 000- resistor and a 0.50-µF capacitor are connected in series with a switch. The time
constant for such a circuit, designated by the Greek letter, , is defined as the time required to charge the
capacitor to 63% of its capacity after the switch is closed. What is the value of  for this circuit?
a.6.0  10
9
s c.1.7

7
s
b.1.7  10

10
s d.1.5

3
s
____ 46. The following three appliances are connected to a 120-V house circuit: i) toaster, 1 200 W, ii) coffee pot, 750
W, and iii) microwave, 800 W. If all were operated at the same time, what total current would they draw?
a.3.0 A c.10 A
b.5.0 A d.23 A
____ 47. What is the maximum number of 60-W light bulbs you can connect in parallel in a 120-V home circuit
without tripping the 30-A circuit breaker?
a.11 c.59
b.35 d.3 600
____ 48. A hair dryer draws 1 200 W, a curling iron draws 800 W, and an electric light fixture draws 500 W. If all
three of these appliances are operating in parallel on a 120-V circuit, what is the total current drawn?
a.19.4 A c.25.4 A
b.20.8 A d.36.7 A
ID: A
1
DC Circuits
MULTIPLE CHOICE
1. C
2. B
3. A
4. C
5. A
6. A
7. D
8. A
9. A
10. C
11. D
12. B
13. A
14. D
15. A
16. D
17. B
18. C
19. D
20. C
21. C
22. D
23. C
24. B
25. C
26. B
27. A
28. B
29. C
30. B
31. A
32. D
33. A
34. C
35. C
36. C
37. A
38. B
39. B
40. C
ID: A
2
41. A
42. C
43. C
44. B
45. D
46. D
47. C
48. B