Magnetism

Question 1

Ampere-turn

Answer 1

basic unit of measurement for magnetism
number of turns of wire x current flow

Question 2

Demagnetized

Answer 2

removal of magnetism from an object

Question 3

Electromagnets

Answer 3

magnets that rely on electricity to become magnetized

Question 4

Electron spin patterns

Answer 4

pattern or direction in which electrons spin as they orbit the nucleus of an atom

Question 5

Flux

Answer 5

magnetic lines of force

Question 6

Flux density

Answer 6

number of magnetic lines contained in a certain area

Question 7

Left-hand rule

Answer 7

rule used for determining the polarity of an electromagnet when direction of current flow is known (in a conventional flow circuit)

Question 8

Lines of flux

Answer 8

lines of magnetic force

Question 9

Lodestones

Answer 9

natural magnets

Question 10

Magnetic domains/molecules

Answer 10

section within a magnetic material where atoms are aligned to produce a north or south south polarity

Question 11

Magnetomotive force

Answer 11

magnetic force produced by current flowing through a conductor or coil

Question 12

Permanent magnets

Answer 12

magnets that don’t require an external force to maintain their magnetic properties

Question 13

Permeability

Answer 13

measurement of a material’s ability to to conduct magnetic lines of flux; standard is air w/a permeability of 1

Question 14

Reluctance

Answer 14

resistance to magnetism

Question 15

Residual magnetism

Answer 15

amount of magnetism left in an object after magnetizing force has been removed

Question 16

Saturation

Answer 16

maximum amount of magnetic flux a material can hold
when all the molecules of a magnetic material are lined up

Question 17

What is the magnetic polarity of the geographic north

Answer 17

south polarity

Question 18

What is the magnetic polarity of the geographic south

Answer 18

north polarity

Question 19

Angle of declination

Answer 19

angular difference between the geographic pole and the magnetic pole

Question 20

T/F: Energy is required to create a magnetic field but no energy is required to maintain a magnetic field

Answer 20

True

Question 21

List the 3 natural magnets

Answer 21

Iron (Fe)
Nickle (Ni)
Cobalt (Co)

Question 22

List some ferromagnetic materials

Answer 22

Fe
Ni
Co
Mn (Manganese)

Question 23

Ferromagnetic

Answer 23

easily magnetized materials

Question 24

List some paramagnetic materials

Answer 24

Platinum (Pt)
Titanium (Ti)
Chromium (Cr)

Question 25

Paramagntetic

Answer 25

materials that can be magnetized but not as easily as those that are ferromagnetic

Question 26

List some diamagnetic materials

Answer 26

Copper (Cu) Brass Antimony (Sb)

Question 27

Diamagnetic

Answer 27

materials that cannot be magnetized

Question 28

What are the best types of materials to make into magnets and why

Answer 28

ferrites because they are insulators

Question 29

T/F flux lines surround the entire magnet

Answer 29

true

Question 30

what is the law of electromagnetism

Answer 30

when an electric current flows through a conductor, a magnetic field is formed around the conductor

Question 31

what happens to the electromagnetic field once current stops

Answer 31

it no longer exists

Question 32

air core magnet

Answer 32

EM in which a coil is wrapped around a nonmagnetic material

Question 33

iron core magnet

Answer 33

EM in which coil is wrapped around magnetic material

Question 34

which has a stronger magnetic field: air core or iron core

Answer 34

iron core

Question 35

coercive force

Answer 35

how well a material retains it's magnetism

Question 36

magnetomotive force formula

Answer 36

phi x rel

Question 37

what are ways to demagnetize materials

Answer 37

place object in the field of a strong electromagnet that is connected to an AC circuit strike it heat it

Question 38

Solenoid

Answer 38

when a coil is wrapped around around a material for the purpose of producing an electromagnetic field

Question 39

Magnetic field is directly or indirectly proportional to it's ampere-turns

Answer 39

directly (more ampere-turns means a stronger field)