Page 42 - Teach Yourself Electricity and Electronics
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22 Basic physical concepts
18. In some batteries, chemical energy can be replenished by:
A. Connecting it to a light bulb.
B. Charging it.
C. Discharging it.
D. No means known; when a battery is dead, you have to throw it away.
19. A changing magnetic field:
A. Produces an electric current in an insulator.
B. Magnetizes the earth.
C. Produces a fluctuating electric field.
D. Results from a steady electric current.
20. Light is converted into electricity:
A. In a dry cell.
B. In a wet cell.
C. In an incandescent bulb.
D. In a photovoltaic cell.
