Chapter 7

Question 1

Electric Field

Answer 1

surrounds an electric charge and
exerts a force on other electric charges

Question 2

magnetism

Answer 2

refers to the properties and
interactions of magnets.

Question 3

magnetic field

Answer 3

region of space that
surrounds a magnet
and exerts a force on
other magnets and
objects made of
magnetic materials.

Question 4

Magnetic fields can be represented with ___

Answer 4

magnetic field lines

Question 5

magnetic poles.

Answer 5

regions of a magnet that exert the strongest
force

Question 6

N to N and S to S

Answer 6

Repel

Question 7

N to S and S to N

Answer 7

attract

Question 8

The magnetic field always
points away from

Answer 8

north and towards south

Question 9

which order is top and bottom

Answer 9

south at the top, north at the bottom

Question 10

what can be made into a magnet

Answer 10

iron, cobalt, and nickel

Question 11

What happens to the magnetic force as the distance
between two magnetic poles decreases?

Answer 11

it increases

Question 12

Atoms at the north pole of a magnet have

Answer 12

north and south magnetic poles.

Question 13

Which metal cannot be attracted by a magnet?

Answer 13

aluminum

Question 14

Which of these descriptions of magnetic force is not
correct?

Answer 14

A south pole repels a north pole.

Question 15

Which statement describes the magnetic field lines
around Earth?

Answer 15

They point toward Earth’s south magnetic
pole near its geographic north pole.

Question 16

Electric current produces a

Answer 16

magnetic feild

Question 17

The
field’s direction depends on

Answer 17

the currents direction

Question 18

electromagnetic force

Answer 18

the attractive or
repulsive force between electric charges and magnets

Question 19

electromagnetism.

Answer 19

interaction between electric charges and
magnets

Question 20

solenoid.

Answer 20

single wire wrapped into a cylindrical wire coil

Question 21

electromagnet

Answer 21

temporary magnet created
when there is a current in a wire coil.

Question 22

electric motor

Answer 22

device that changes
electrical energy into mechanical energy.

Question 23

What is the purpose of the iron core in an
electromagnet?

Answer 23

It increases the magnetic field in the coil.

Question 24

What happens to an electromagnet when it is placed in a
magnetic field?

Answer 24

It rotates to align with the field.

Question 25

What conversion is an electric motor designed to do?

Answer 25

electrical energy into mechanical energy

Question 26

What is the purpose of the commutator?

Answer 26

reverse the current in the coil

Question 27

voltage difference:

Answer 27

the force that causes electric charges to flow; measured in volts

Question 28

electromagnetic induction.

Answer 28

The generation of an electric current by a changing magnetic field

Question 29

generator

Answer 29

uses electromagnetic induction to transform mechanical energy into electrical energy.

Question 30

Direct current (DC)

Answer 30

electric current that is always in one direction through a wire.

Question 31

Alternating current (AC)

Answer 31

electric current that reverses the direction in a regular pattern.

Question 32

transformer

Answer 32

device that increase or decrease the voltage of an alternating current.

Question 33

What is the purpose of a transformer?

Answer 33

Increases or decreases the voltage of AC.

Question 34

Why are transformers important for getting electrical energy to your home?

Answer 34

They reduce waste due to resistance.

Question 35

What conversion is an electric generator designed to do?

Answer 35

mechanical to electrical

Question 36

The regions on a magnet where the magnetic force is strongest are called .

Answer 36

magnetic poles

Question 37

The south pole of a magnet will the south pole of another magnet.

Answer 37

repel

Question 38

A device that uses an electromagnet to measure electric current is a(n) .

Answer 38

galvanometer

Question 39

A device used to increase or decrease the voltage of current in a power line is a(n) .

Answer 39

transformer

Question 40

A switch that regularly reverses the current in some motors is a(n)

Answer 40

commutator

Question 41

Current that flows in only one direction through a wire is called

Answer 41

direct current

Question 42

A large wheel that rotates when pushed by water, wind, or steam.

Answer 42

turbine

Question 43

When current in a circuit reverses its direction in a regular pattern, it is called .

Answer 43

alternating current

Question 44

The properties and interactions of magnets are referred to as .

Answer 44

magentism

Question 45

Groups of aligned atoms in a magnet are called .

Answer 45

magnetic domains

Question 46

A(n) is formed by placing a piece of iron inside a current-carrying coil of wire

Answer 46

electromagnet

Question 47

A machine that changes electrical energy to mechanical energy is a(n) used to do work, such as turning a fan.

Answer 47

electric motor

Question 48

13. A device that produces an electric current by rotating a coil of wire in a magnetic field is a(n) .

Answer 48

generator

Question 50

The process by which moving a wire through a magnetic field produces an electric current is .

Answer 50

electromatic induction