Review
____
1. When more devices are added to a series circuit, the total circuit resistance:
a. decreases.
b. increases.
c. stays the same.
d. may increase or decrease, depending on the device.
____
2. The voltage drop across each resistor in the circuit below is ____ volts.
a.
b.
c.
d.
1.5
3
2
9
____
3. The current in a series circuit:
a. decreases to zero as it travels through the circuit.
b. is the same at all points in a circuit.
c. is greatest in the resistor with the highest resis
resistance.
d. is greatest in the resistor with the lowest resistance.
____
4. A student connects six 3-ohm
ohm light bulbs in series to a 99-volt
volt battery. The total circuit current is ____ ampere(s).
a. 0.5
b. 2
c. 4.5
d. 18
Study the circuit diagrams shown below (all bulbs are identical):
Figure 14-2A
____
5. Which of the circuit diagrams shown in Figure 14
14-2A is a series circuit?
a. I only
b. II only
c. III only
d. I and II only
____
6. Which of the circuit diagrams shown in Figure 14
14-2A is a parallel circuit?
a. I only
b. II only
c. III only
d. I and II only
____
7. When a new branch containing a resistor is added to a parallel circuit, the total circuit resistance:
a. decreases.
b. increases.
c. stays the same.
d. may increase
ase or decrease, depending on the device.
____
9. A lamp has a short circuit.. Which of the following statements best describes the lamp’s circuit?
a. The circuit is drawing a large amount of current.
b. The circuit has a path of very low resista
resistance.
c. The lamp will not turn on.
d. All of the above
ohm resistor pictured below is ____ volt(s).
____ 10. The voltage across the 1-ohm
a. 1/3
b. 2/3
c. 1
d. 3
____ 13. As the distance between two positively charged objects increases, the force between them:
a. increases.
c. cannot be determined.
b. decreases.
d. remains the same.
____ 14. The electric force between a 5-coulomb
coulomb charge and a 11-coulomb
coulomb charge 9,000 meters apart is:
a. 5,000,000 newtons.
b. 666 newtons.
c. 556 newtons.
d. 0.000556 newtons.
1. What is the potential difference across a 5 ohm resistor which carries a current of 5 A?
a. 100 V
b. 25 V
c. 4 V
d. 1 V
7. A wire carries a steady current of 0.1 A over a period of 20 s. What total charge passes through the wire in
this time interval?
a. 200 C
b. 20 C
c. 2.0 C
d. 0.005 C
8. If a 500 W heater carries a current of 4.0 A, what is the voltage across the ends of the heating element?
a. 2000 V
b. 125 V
c. 250 V
d. 0.008 V
11. If a lamp is measured to have a resistance of 120 ohms when it operates at a power of 100 W, what is the
applied voltage?
a. 110 V
b. 120 V
c. 125 V
d. 220 V
13. An electric toaster requires 1100 W at 110 Volts. What is the resistance of the heating coil?
a. 7.5
b. 9.0
c. 10.0
d. 11.0
18. Three resistors having values of 4.0, 6.0 and 8.0 ohms, are connected in series. What is their equivalent
resistance?
a. 18.0 ohms
b. 8.0 ohms
c. 6.0 ohms
d. 1.8 ohms
20. Three resistors connected in parallel have individual values of 4.0, 6.0 and 10.0 ohms, respectively. If this
circuit is connected to a 12.0 V battery what is the current in the 10 ohm resistor?
a. 0.55 A
b. 5.2 A
c. 1.2 A
d. 2.0 A
22. The following three appliances are connected in parallel to a 120 volt house circuit:
i)
toaster, 1200 W,
ii)
coffee pot, 750 W, and
iii)
microwave, 600 W.
If all were operated at the same time what total current would they draw?
a. 3 A
b. 5 A
c. 10 A
d. 21 A
24. Two resistors of values 6 and 12 ohms are connected in parallel. This combination in turn is hooked in
series with a 4 ohm resistor. What is the overall resistance of this combination?
a. 0.5 ohms
b. 2.0 ohms
c. 8.0 ohms
d. 22.0 ohms
27. What is the maximum number of 100 Watt lightbulbs you can connect in parallel in a 120 V home circuit
without burning out the 20 A fuse?
\\\\\\\\ a. 11 bulbs
b. 17 bulbs
c. 23 bulbs
d. 29 bulbs
200kΩ
A
3000Ω
B
1000Ω
Parallel or series
What is the equivalent resistance?_____
What is the total current?______
How much voltage is dropped in between A & B?
What is the current across the 3000Ω resistor?
15 V
25Ω
30Ω
=====arallel or series?
Equivalent resistance?
10Ω
What is the current across the 25 ohm resistor?
====
What is the total current?
9V
3Ω
Resistance through parallel portion?
2Ω
Equivalent resistance?
What is the total current?
5Ω
6Ω
15 V