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Flashcards in Chapter 7 TEST Deck (22):
0

The North Pole of one magnet is attracted to what pole on a different magnet?

The opposite one... The South Pole!

1

You can increase the strength go an electromagnet by...?

Adding loops to the coil

2

An electric fan plugged into a wall outlet runs on what kind of current?

Alternating current

3

The current in an electric motor comes from what?

The amount of current flowing

4

Reaction between like poles? Reaction between unlike poles?

Same poles repel and opposite poles attract

5

What three materials can be used to create a magnet?

Iron cobalt and nickel

6

When a current is passed through a coil of wire with a piece of iron inside what is formed?

And electromagnet is formed

7

An electromagnet is a what?

A temporary magnet

8

Adding more turns to the wire coil does what to the strength of an electromagnet?

Increases the strength

9

Electromagnets change electrical energy into what kind?

Electrical to mechanical energy

10

And electric motor contains what that is free to rotate between the poles of a permanent, fixed magnet?

It contains an electromagnet that is free to move

11

An electric motor changes what energy into mechanical energy?

Electric to mechanical energy

12

A coils magnetic field can be flipped by doing what in the coil?

Reversing the direction of the current flips the magnetic field

13

In a motor, a reversing switch that rotates with an electromagnet is called what?

Commutator

14

In a motor, the stronger the magnetic field in the coil, the weaker/stronger the force between the perme at magnet and the electromagnet?

The stinger magnetic field in the coil the stronger the force is

15

The speed of an electric motor can be controlled by varying the amount of what to the motor?

Electric current

16

A generator contains what three parts?

Permant magnet, electromagnet and a source of mechanical energy

17

When the wire loop of a what turns an electric current is produced?

Generator

18

The current produced by a generator is what kind of current?

Alternating

19

A motor uses or creates an electric current as it turns?

Creates

20

A deuce that increase or decreases voltage of electric current passing through a power line is a what?

Transformer

21

If the secondary coil of a transformer has more turns that the primary coil, the transformer is a what transformer?

Step- up transformer