Deck 4: Magnetism

Question 1

The strength of an electromagnet is primarily proportional to its .

A) length
B) ampere-turns
C) diameter
D) core resistance

Answer 1

B

Question 2

Lodestone is a name for a naturally occurring magnetic material that is also called .

A) lead
B) magnetism
C) copper
D) magnetite

Answer 2

D

Question 3

The amount of magnetism left in a material after the magnetizing force has stopped is called .

A) permeability
B) reluctance
C) saturation
D) residual magnetism

Answer 3

D

Question 4

Earth contains magnetic poles.

Question 5

The regions formed in the molecular structure of magnetic metals are sometimes called magnetic .

A) quarks
B) spins
C) domains
D) atoms

Question 6

The north pole of a compass needle points in the direction of the south geographic pole.

Question 7

Magnetic lines of force are referred to as .

A) flux
B) spin
C) reluctance
D) bands

Question 8

The north magnetic pole of a compass needle is attracted to the magnetic pole of the earth.

A) north
B) south
C) east
D) west

Question 9

What type of magnets do not require any power or force to maintain their field?

A) electromagnets
B) permanent magnets
C) temporary magnets
D) domain magnets

Question 10

Magnetism can be explained in terms of spin patterns.

A) electron
B) neutron
C) proton
D) quark

Question 11

A basic law of magnetism states that unlike poles and like poles .

A) attract; repel
B) repel; attract

Question 12

In the English system of measure, magnetic strength is measured in terms of .

A) residual magnetism
B) reluctance
C) permeability
D) flux density

Question 13

The measure of a material's ability to be magnetized is called .

A) permeability
B) reluctance
C) saturation
D) residual magnetism

Question 14

The measure of a material's resistance to magnetism is known as .

A) permeability
B) reluctance
C) saturation
D) residual magnetism

Question 15

When a magnetic material's molecules are all lined up, and increases in current flow no longer cause increases in magnetic field strength, the material has reached .

A) permeability
B) reluctance
C) saturation
D) residual magnetism

Question 16

If a permanent magnet is cut into pieces, each piece a separate magnet.

A) is not
B) is

Question 17

The angular difference between true north and magnetic north is known as the angle of .

A) polarity
B) retribution
C) declination
D) magnetism

Question 18

What type of magnet depends on flowing current to produce a magnetic field?

A) electromagnet
B) permanent magnet
C) temporary magnet
D) domain magnet

Question 19

The three substances that form natural magnets are .

A) iron, boron, and cobalt
B) copper, iron, and cobalt
C) copper, nickel, and boron
D) iron, nickel, and cobalt

Question 20

Man-made permanent magnets retain their magnetism than natural magnets.

A) less
B) longer

Question 21

Of the three basic classifications of magnetic materials, materials are either metal or nonmetal materials that cannot be magnetized.

Question 22

If an object is placed in the field of an strong electromagnet connected to an AC line, the object will be .

A) demagnetized
B) magnetized

Question 23

To locate the north pole of an electromagnet, use the hand rule.

A) left
B) right

Question 24

Of the three basic classifications of magnetic materials, materials are metals that are most easily magnetized.

Question 25

In the English system, the total force producing a magnetic field is the .

A) magnetomotive force
B) reluctance
C) permeability
D) flux density