Chapter 7 Test (Magnetism and Its Uses)

Which of the following describes the direction of the electric current in DC?

• The flow changes regularly.

• The flow changes irregularly.

• The flow shows no pattern.

• The flow is in one direction.

Which of the following elements is a magnetic material?

• aluminum

• copper

• tin

• nickel

The primary coil (plug end) has twenty turns and the secondary coil (light) has two turns. What is the voltage at the lamp?

• 15 V

• 120 V

• 12 V

• 1200 V

The primary coil (plug end) has twenty turns and the secondary coil (light) has two turns. What is the current at the lamp?

• 12 A

• 15 A

• 96 A

• 1.5 A

Generators convert ________.

• A. chemical energy to electrical energy

• B. mechanical energy to thermal energy

• C. mechanical energy to electrical energy

• D. thermal energy to electrical energy

The magnetic field of an electromagnet can be increased by ________.

• changing the direction of the current

• decreasing the current

• increasing the number of coils

• decreasing the number of coils

In a stereo system, the energy conversion is ________.

• A. electrical energy to sound energy

• B. electrical energy to magnetic energy

• C. electrical energy to thermal energy

• D. electrical energy to potential energy

What does this illustration represent?

• magnetic material that is not magnetized

• magnetic material that is magnetized

• non-magnetic material

• arrangement of atoms in a domain

In this illustration, the magnetic field is strongest ______.

• near either pole

• near the north pole

• near the south pole

• halfway between the poles

Which is necessary for a transformer to function?

• copper wiring

• a DC current

• an AC current

• a permanent magnet