A Beka Physical Science Chapter 14

Front 1

rock that naturally acted as a compass

Back 1

lodestone

Front 2

any object capable of attracting iron, steel, etc. by magnetic force

Back 2

magnet

Front 3

the property of attracting objects by magnetic force

Back 3

magnetism

Front 4

regions of concentrated magnetism

Back 4

poles

Front 5

the magnetic pole that points north

Back 5

north pole

Front 6

the magnetic pole that points south

Back 6

south pole

Front 7

says that unlike poles attract, while like poles repel

Back 7

law of magnetic poles

Front 8

magnetic poles always exist ____ _________

Back 8

in pairs

Front 9

the region surrounding a magnet in which other objects are affected by magnetism

Back 9

magnetic field

Front 10

imaginary lines that indicate the direction and strength of a magnetic field

Back 10

lines of flux

Front 11

states that force between two magnetic poles is directly related to the product of the pole strengths and inversely related to the square of the distance between them

Back 11

law of magnetic force

Front 12

scientist who discovered the law of magnetic force

Back 12

Charles de Coulomb

Front 13

formula for law of magnetic force

Back 13

Front 14

a train that never touches its tracks

Back 14

maglev train

Front 15

the extent to which a material can absorb or channel lines of magnetic flux (how easy it is to magnetize)

Back 15

permeability

Front 16

does a permeable material increase or decrease magnetic force between two objects

Back 16

depends on its placement

Front 17

how magnetic fields are produced

Back 17

the movement of electrons and other charged particles

Front 18

describe the motion of electrons within an atom

Back 18

quantum numbers

Front 19

the most important cause of magnetism

Back 19

electron spin

Front 20

three motions in atoms that cause magnetism

Back 20

electrons spinning on their axes, electrons orbiting the nucleus, the nucleus spinning on its axis

Front 21

a group of aligned atoms having a single magnetic field

Back 21

domain

Front 22

a nucleus which is constantly reversing direction of spin because it is absorbing radio waves

Back 22

nuclear magnetic resonance (NMR)

Front 23

medical use of nuclear magnetic resonance to produce a 3-D image of the inside of a body

Back 23

magnetic resonance imaging

Front 24

states that the magnetic field of a magnet is the sum of the fields of thousands of magnetic domains

Back 24

domain theory

Front 25

a magnetic substance can only become a magnet if what

Back 25

its domains are mostly aligned

Front 26

substances with no unpaired electrons that are slightly repelled by either end of a magnet

Back 26

diamagnetic substances

Front 27

substances with one unpaired electron that are weakly attracted to magnets

Back 27

paramagnetic substances

Front 28

substances that have several unpaired electrons and are strongly attracted to magnets

Back 28

ferromagnetic substances

Front 29

substances that can be quickly magnetized

Back 29

magnetically soft substances

Front 30

the kind of magnet made from a magnetically soft material

Back 30

temporary magnet

Front 31

a magnet that quickly loses its magnetism when removed from a magnetic field

Back 31

temporary magnet

Front 32

materials whose domains strongly resist change

Back 32

magnetically hard substances

Front 33

magnets made from magnetically soft substances

Back 33

permanent magnets

Front 34

common magnetically soft substance

Back 34

iron

Front 35

common magnetically hard substance

Back 35

alnico

Front 36

creating a magnet by stroking it with another magnet

Back 36

magnetizing by contact

Front 37

the kind of magnet created by contact

Back 37

permanent or temporary

Front 38

creating a magnet by placing an object within a magnetic field

Back 38

magnetizing by induction

Front 39

the kind of magnet created by induction

Back 39

temporary

Front 40

creating a magnet by placing it in an electric field

Back 40

magnetizing by electricity

Front 41

discovered that electricity flowing in a wire has a magnetic field around it

Back 41

Hans Christian Oersted

Front 42

branch of science that studies electricity and magnetism together

Back 42

electromagnetism

Front 43

says that if the thumb of the left hand is pointed along a wire in the direction of electron movement the fingers encircle the conductor in the same direction as the magnetic field

Back 43

left-hand rule

Front 44

device that produces a strong magnetic field when electricity passes through it

Back 44

electromagnet

Front 45

invented the electromagnet

Back 45

William Sturgeon

Front 46

magnetically soft object placed within the coils of an electromagnet to strengthen its field

Back 46

core

Front 47

how to determine the strength of an electromagnet

Back 47

directly related to the square of the current and proportional to the number of loops of wire around the core

Front 48

ways to cause a permanent magnet to lose its magnetism

Back 48

striking repeatedly with a hammer, heating to a high temperature, storing with like poles together

Front 49

the temperature at which a ferromagnetic material's domains disappear

Back 49

Curie point

Front 50

can be put between magnets that are being stored to help preserve their magnetism

Back 50

keeper

Front 51

magnetism used to store information on banking cards

Back 51

magnetic stripes

Front 52

force in a magnetic field that changes the path of a charged particle moving through the field

Back 52

deflecting force

Front 53

a navigational device consisting of a magnet free to swing horizontally so it always points north

Back 53

magnetic compass

Front 54

discovered that a compass points north because the earth has a magnetic field

Back 54

William Gilbert

Front 55

book Gilbert published to explain that the earth is a magnet

Back 55

De Magnete

Front 56

what is backwards about the earth's poles

Back 56

geographic north, the north pole, is south-seeking, not north-seeking, and vice versus

Front 57

the difference between where a compass tells you the north pole is and where the geographic north pole actually is (greater the farther north you are)

Back 57

angle of declination

Front 58

lines on a map that connect points of equal declination

Back 58

isogonic lines

Front 59

the line on a map connecting all points where a compass points to true north

Back 59

agonic line

Front 60

phenomenon which causes a vertically free compass to point toward the earth in the north

Back 60

magnetic dip or inclination

Front 61

lines on a map that connect points of equal inclination

Back 61

isoclinic lines

Front 62

the angle of inclination at the poles

Back 62

90 degrees (straight down)

Front 63

imaginary lines where there is no inclination

Back 63

magnetic equator

Front 64

devices that measure the strength of magnetic materials

Back 64

magnetometers

Front 65

the extent of a planet's magnetic field in space

Back 65

magnetosphere

Front 66

stream of plasma from the sun that distorts the magnetosphere of the earth

Back 66

solar wind

Front 67

outer boundary of the magnetosphere

Back 67

magnetopause

Front 68

two large, donut-shaped belts of high-speed charged particles

Back 68

Van Allen radiation belts (trapped particles from the solar wind)

Front 69

display of shimmering light in the sky

Back 69

aurora

Front 70

name for northern aurora

Back 70

aurora borealis

Front 71

name for southern aurora

Back 71

aurora australis

Front 72

planets that are not magnetic

Back 72

Venus and Mars

Front 73

planet with the largest magnetic field

Back 73

Jupiter

Front 74

planet whose magnetic poles are near the equator

Back 74

Uranus

Front 75

planet whose magnetic poles match its geographic poles

Back 75

Saturn

Front 76

planet with a stronger south pole than north

Back 76

Neptune

Front 77

celestial body with a violently changing magnetic field

Back 77

sun