Electricity and Magnetism Concepts

What is the main difference between an electric motor and an electric generator?

• Motors create heat, generators create light.

• Motors turn electrical energy into movement, while generators turn movement into electrical energy.

• Motors use magnets, generators use batteries.

• Motors are small, generators are large.

What happens to the direction of the electric current produced by a generator as the coil rotates?

• It always flows in the same direction.

• It stops and starts.

• It reverses direction with every half turn.

• It gets stronger and weaker but never changes direction.

What is the term for how many times per second alternating current changes its direction?

• Voltage

• Amperage

• Frequency

• Resistance

Which of these would make an electric generator produce more electricity?

• Using fewer loops of wire.

• Using a weaker magnet.

• Making the wire loops smaller.

• Making the coil rotate faster.

Why is electricity sent through power lines at very high voltages?

• To make it safer for people.

• To make the electricity travel faster.

• To reduce the amount of power lost as heat.

• To make the wires glow brighter.

What is the main job of a transformer in an electrical system?

• To make electricity glow.

• To change the voltage of electricity.

• To store electricity for later use.

• To clean the electricity.

How do transformers change the voltage of electricity?

• By using magnets to push and pull the electricity.

• By changing the color of the electricity.

• By using mutual inductance between two coils.

• By adding more electricity to the wires.

What kind of transformer increases the voltage of electricity?

• A step-down transformer.

• A step-up transformer.

• A charging transformer.

• A mutual transformer.