##### 1. Resistance in a circuit is generally measured in units of ____.

- W
- Ð
- K
- Z

##### 2. Which of the following is the correct expression of Ohm’s Law?

- I = R/V
- R= P/V
- I= P/V
- I = V/R

##### 3. An operating lamp draws a current of .4 ampere. The amount of charge passing through the lamp in 10 seconds is?

- .045 C
- 4.0 C
- 5.0 C
- 6.24 C

##### 4. To increase the brightness of a desk lamp a student replaces a 50 W light bulb with a 100 W light bulb. Compared to the 60 W light bulb the 100 W light bulb has?

- Less resistance and draws more current
- Less resistance and draws less current
- More resistance and draws more current
- More resistance and draws less current

##### 5. An electric dryer consumes 6.0 x 10^{6} joules of energy when operating at 220 volts for 30 minutes. During operation the dryer draws a current of approximately?

- 10 A
- 15 A
- 20 A
- 25 A

##### 6. When 8.0 electronvolt photons strike a photo emissive surface, the maximum kinetic energy of ejected photoelectrons is 6.0 electronvolts. The work function of the photo emissive surface is

- .01 eV
- 1.0 eV
- 2.0 eV
- 3.0 eV

##### 7. A high resistance is connected in series with the internal coil of a galvanometer to make?

- An ammeter
- A motor
- A generator
- A voltmeter

##### 8. In a transformer, two coils are wound around a common iron core. To operate properly the transformer requires

- More turns in the secondary coil than in the primary coil
- More turns in the primary coil than in the secondary coil
- A direct current source connecting to the secondary coil
- An alternating current source connecting to the primary coil

##### 9. Which device can be used to increase voltage from a source of direct current?

- Generator
- Electroscope
- Induction coil
- Mass spectrometer

##### 10. The transformer on a power pole steps down the voltage from 10,800 volts to 120 volts. If the secondary coil contains 360 turns, how many turns are found on the primary coil?

- 603
- 900
- 15,000
- 32,400

##### 11. An electric motor draws 150 amperes of current while operating at 240 volts. What is the power rating of this motor?

- 2.1 x 10
- 2.7 x 10
- 3.6 x 10
- 4.1 x 10
^{5}W

##### 12. What is the potential difference across a 2.0 ohm resistor that draws 2.0 coulombs of charge per second?

- 1.0 V
- 2.0 V
- 3.0 V
- 4.0 V

##### 13. If a 15-ohm resistor is connected in parallel with a 30 ohm-resistor, the equivalent resistance is?

- 5W
- 7W
- 10W
- 15W

##### 14. A metal wire has length L and cross-sectional area A. The resistance of the wire is directly proportional to

- L/A
- A/L
- L + A
- L x A

##### 15. A wire carries a current of 2.0 amperes. How many electrons pass a given point in this wire in 1.0 second?

- 1.3 x 10
^{18} - 2.0 x 10
^{18} - 1.3 x 10
^{19} - 2.0 x 10
^{19}

##### Answer Key

###### 1. A

2. D

3. C

4. A

5. B

6. C

7. D

8. D

9. C

10. D

11. C

12. D

13. C

14. A

15. C

by Enoch Morrison | Last Updated: October 30, 2018