Download Chapter 13: Electric Circuits

Chapter 13: Electric Circuits
1. A household circuit rated at 120 Volts is protected by a fuse rated at 15 amps. What is the
maximum number of 100 watt light bulbs which can be lit simultaneously in parallel in this
circuit without blowing the fuse?
A. 4
B. 8
C. 18
D. 20
E. 24
2. The resistance of a circuit element is a measure of
A. the total energy of the charges in the circuit element.
B. the amount of work that an electron can perform.
C. the ratio of the voltage difference between element ends to the current in the element.
D. the size of the circuit.
3. A certain kind of light bulb carries 1.5 amperes of current when connected to a 120 Volt AC
circuit. What is its power rating?
A. 240 W
B. 180 W
C. 80 W
D. 100 W
4. The resistance of a 25 watt bulb is ______that of a 100 watt bulb, if both run on the same
voltage.
A. one half
B. one fourth
C. four times
D. double
5. Two light bulbs are installed in two sockets, the sockets are connected in series, and power is
then applied to the combination so that both bulbs light. If one of the bulbs is then removed from
its socket, the other one will
A. get brighter.
B. remain equally bright.
C. get dimmer.
D. go out.
6. What is the best way to ensure that a 40 watt bulb and a 60 watt bulb have the same voltage
applied to them?
A. Connect the bulbs in series with the power supply (
)
like this:
40
60
B. Connect the bulbs in parallel with the power supply like this:
40
60
C. Separately connect the bulbs to two power supplies rated at the same voltage
40
60
D. Can’t be done: different wattage bulbs must always have different voltages.
7. A 40 W bulb and a 60 W bulb are connected in series with a 120 V power source. Which of
the following is true for this arrangement?
A. The 40 W bulb is brighter than the 60 W bulb.
B. The 60 W bulb is brighter than the 40 W bulb.
C. The 60 W bulb is brighter than it would be if the 40 W bulb were replaced by a wire.
D. The 40 W bulb is brighter than it would be if the 60 W bulb were replaced by a wire.
8. A 40 W bulb and a 60 W bulb are connected in parallel, and powered by 120 V from
household wiring (see sketch). If the 40 W bulb is then removed from its socket, the 60 W bulb
will
A.
B.
C.
D.
get brighter.
remain equally bright.
get dimmer.
go out.
9. What is the best way to ensure that a 40 watt bulb and a 60 watt bulb have the same
current within them?
A. Connect the bulbs in series with the power supply, like this:
B. Connect the bulbs in parallel with the power supply, like this:
C. Separately connect the bulbs to two batteries having the same voltage
D. Can’t be done: different wattage bulbs must always have different currents.
10. Bulbs A, B, C, and D are connected to a battery (
greatest voltage is
) as shown. The bulb with the
A
C
A.
B.
C.
D.
bulb A.
bulb C.
both bulb A and bulb C.
both bulb C and bulb D.
11. An ohm is equal to which of these?
A. a volt
B. a coulomb per second
C. a volt per ampere
D. an ampere per second
12. One ampere is equivalent to:
A. 1 V/m.
B. 1 N/C.
C. 1 J/s.
D. 1 C/s.
E. 1 ohm/volt.
D
B
13. A 12 ohm resistor and a 24 ohm resistor are connected in series in a circuit with a 6.0 volt
battery. Assuming negligible internal resistance in the battery, the current in the 12 ohm resistor
will be
A. 6.0 A.
B. 2.0 A.
C. 0.50 A.
D. 0.25 A.
E. 0.167 A.
14. A 12 ohm resistor and a 24 ohm resistor are connected in parallel across a 6.0 V battery.
The correct statement from the following is
A. the current is the same in each resistor.
B. the power dissipated is the same in each resistor.
C. the voltage difference between the ends of each resistor is the same.
D. the larger current is in the larger resistor.
15. A 12 ohm resistor and a 24 ohm resistor are connected in series with a 6.0 V battery. The
correct statement is
A. the voltage difference between the ends of each resistor is the same.
B. the current in each resistor is the same.
C. the power dissipated in each resistor is the same.
D. the smaller resistor carries the larger current.
16. A 75 watt bulb and a 150 watt bulb are connected in parallel and the combination is
connected to a 120 V line. The bulb that will glow more brightly is the
A. 75 watt bulb.
B. 150 watt bulb.
C. both will glow with the same brightness.
17. The voltage drop across a resistor is 3.0 V for a current of 1 A in the resistor. What is the
current that will produce a voltage drop of 9.0 V across the resistor?
A. 1 A
B. 3 A
C. 0.33A
D. 27 A
18. Three bulbs have power ratings for use on a 120 volt line: 60 watt, 100 watt and 150 watt.
The one with the largest value of resistance has power rating
A. 60 W.
B. 100 W.
C. 150 W.
D. all have the same resistance.
19. A 100 watt bulb is rated for use in a 120 volt line. During a brownout the actual voltage
drops to 100 V. The actual power dissipated in the bulb under these conditions is
A. 120 W.
B. 100 W.
C. 83.3 W.
D. 69.4 W.
E. 48.2 W.
20. A heater is rated to dissipate 1800 W when connected to a 120 V source. The current drawn
by the device is
A. 1800 A.
B. 120 A.
C. 30 A.
D. 15 A.
E. 0.067 A.
21. You have exactly 4 resistors: one 3 , one 4 one 5 , and one 6 . How can you
combine these to make a 2 resistor? (The symbol stands for "ohm".)
A. Connect the 3 resistor in series with the 5  resistor.
B. Connect the 3 resistor in parallel with the 6  resistor.
C. Connect the 3 resistor in parallel with the 4  resistor.
D. Connect all four resistors in parallel with each other.
E. You can't make a 2 resistor from the ones listed.
22. A one ohm, a two ohm, and a three ohm resistor are connected in series in an electric circuit:
The resistor dissipating the most power will be the ______3______ ohm resistor.
23. A student finds three resistors in the lab: a two ohm, a five ohm, and a 10 ohm resistor. The
smallest value of resistance that the student can make using any one or any combination of the
three resistors is ______1.25______ ohms.