Show:
What's the Static?
It's electric!
Circuit Judge?
Resistance is futile!
100
If you rub a piece of silk with a glass rod, the glass rod acquires a +8 charge. What charge doe the silk acquire?
A. +16 B. +8 C. -8 D.-16
100
What are two ways to make the field of an electromagnet stronger?
A. Replace the iron core with copper, increase the voltage B. Wrap more wire around the iron core, decrease the current C. Increase the voltage, decrease the current D. Wrap more wire around the iron core, increase the voltage.
100
In a parallel circuit with three bulbs,
A. the overall resistance increases if a new branch is added B. current from each bulb has its own path C. the bulbs must all be located on the same branch D. there is only one path for the current to take
100
Which application uses a magnetic field to convert electrical energy to mechanical energy?
A. alternator B. generator C. magnetron D. motor
200
If you rub an ebonite rod with wool , the wool acquires a positive charge. What conclusion can BEST be drawn from this observation?
A. Many negatively charged particles moved from the wool to the ebonite. B. Many negatively charged particles moved from the ebonite to the wool. C. Many positively charged particles moved from the wool to the ebonite. D. Many positively charged particles moved from the ebonite to the wool.
200
You warp a coil of insulated copper wire around an iron rod. Then, you pass a current through the wire. What happens to the iron bar when current is passed through the coil?
A. It becomes permanently magnetized B. It becomes temporarily magnetized C. It becomes electrically charged D. It becomes an electrical insulator
200
In a series circuit with three bulbs, adding another bulb will
A. make all the bulbs dimmer B. make all the bulbs brighter C. make the nearest bulb brighter D. make the nearest bulb dimmer
200
Sarah wraps a coil of insulated copper wire around an iron rod. She then passes a current through the wire. What happens to the iron bar when current is passed through the coil?
A. It becomes electrically charged. B. It becomes an electrical insulator. C. It becomes temporarily magnetized. D. It becomes permanently magnetized.
300
A balloon acquires a charge when rubbed across fur. Why does the electrically charged balloon now attract small bits of paper?
A. The electrical charge on the balloon induces magnetic attraction with bits of paper. B. Charges on the balloon attract charges of like sign on the bits of paper. C. Excess charges on the balloon jump to the bits of paper. D. The charge of the balloon polarizes the charge on the bits of paper.
300
Which application uses a magnetic field to convert electrical energy to mechanical energy?
A. alternator B. magnetron C. generator D. motor
300
Which is NOT a property of magnetic field lines?
A. They form complete loops from pole to pole. B. They can be directly observed. C. They never cross. D. They spread out as they get farther from the magnet.
300
Power is calculated by multiplying voltage by
A. current B. Energy C. Resistance D. Voltage
400
Particles A and B have equal positive charges and are held two meters apart. Where would a negatively charged particle, C, be placed so that it receives no net electrostatic force?
A. anywhere with an equal distance to both A and B. B. anywhere on the line containing both A and B. C exactly one meter from both A and B. D. exactly two meters from both A and B.
400
Bubba is building an electric motor. What does he observe about the current flow while constructing the motor?
A. The current in the coil is moving in a counterclockwise direction. B. The current in the coil is moving in a clockwise direction. C. The current in the coil reverses every 360 degrees. D. The current in the coil reverses every 180 degrees.
400
A stereo speaker vibrates in and out because it is attached to an electromagnet that is moving in and out. The electromagnet is alternately attracted to and repelled from a permanent magnet. What causes the electromagnet to be first repelled from and then attracted to a permanent magnet?
A. The poles of the permanent magnet reverse. B. The permanent magnet is affected by an electrical field. C. The electrical field of the electromagnet changes strength. D. The electrical current to the electromagnet changes direction.
400
According to Ohm’s law, what is the resistance of a light if the voltage is 9.0 volts and the current is 0.30 amps?
A. 0.033 ohms B. 2.7 ohms C. 30 ohms D. 8.7 ohms
500
You rub a metal ball with a cloth and find that the metal ball becomes positively charged. Which of these BEST explains how the ball became charged?
A. Electrons from the ball moved to the cloth. B. Electrons from the cloth moved to the ball. C. Protons from the ball moved to the cloth. D. Protons from the cloth moved to the ball.
500
Permanent magnets are used in generators to induce current in a coil. What determines the direction of the induced current?
A. type of the magnet B. size of the magnet C. movement of the magnet D. strength of the magnet
500
If an electric water heater uses 40 kW of power and runs for 8 hours, what is the total amount of energy used?
a. 5 kilowatt-hours b. 32 kilowatt-hours c. 48 kilowatt-hours d. 320 kilowatt-hours
500
If a household’s voltage is 120 volts, what is the power rating of a light bulb with 0.5 amps of current flowing through it?
A. 120 watts B. 600 watts C. 60 watts D. 6 watts