Deck 1: Magnetism

Question 1

Residual magnetism is a measure of a material's ability to retain magnetism.

Answer 1

False

Question 2

In the ____ system, the term used to describe the total force producing a magnetic field, or flux, is magnetomotive force (mmf).

A) CGS
B) MKS
C) American
D) English

Answer 2

D

Question 3

Flux density is measured in lines per square centimeter.

Answer 3

False

Question 4

____ occurs when all the molecules of the magnetic material are lined up.

A) Permeation
B) Saturation
C) Agreeability
D) Fulfillment

Question 5

The two factors that determine the number of flux lines produced by an electromagnet are the number of ____ and the amount of current flow through the wire.

A) opposing currents
B) turns of wire
C) wires
D) electrons

Question 6

Because they are always able to align themselves north and south, natural magnets became known as "leading stones" or lodestones.

Question 7

When a coil is wound around a nonmagnetic material such as wood or plastic, it is known as a(n) ____ magnet.

A) pseudo (fake)
B) enhanced
C) air-core
D) created

Question 8

A speaker uses three separate magnets. One is a permanent magnet, and two are electromagnets.

Question 9

Magnetic lines of flux repel each other and never cross.

Question 10

There are actually only three substances that form natural magnets: iron, nickel, and ____.

A) copper
B) lead
C) cobalt
D) magnesium

Question 11

Energy is required to create a magnetic field, and energy is required to maintain a magnetic field.

Question 12

A basic law of physics states that whenever an electric current flows through a conductor, a magnetic field is formed around the conductor.

Question 13

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

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

Question 14

For a magnet with an area of 2 square inches and a flux density of 121, what is the pull (in pounds)?

A) 3.361
B) 3.361x10-2
C) 3.361x10-6
D) 3,3610

Question 15

When an object is to be demagnetized, its molecules must be disarranged as they are in a nonmagnetized material.

Question 16

____ will demagnetize an object.

A) Freezing
B) Rubbing
C) Throwing
D) Heating

Question 17

Viability is a measure of a material's willingness to become magnetized.

Question 18

The polarity of an electromagnet can be determined using the ____ rule.

A) left-hand
B) right-hand
C) one-handed
D) two hands

Question 19

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

Question 20

____ materials are either metal or nonmetal materials that cannot be magnetized.

A) Antimagnetic
B) Paramagnetic
C) Ferromagnetic
D) Diamagnetic