10.2 -10.3

Question 1

Magnetic fields are produced by the ______

Answer 1

motion of electrons and other charged particles

Question 2

________ is the most important cause of magnetism in magnetic materials

Answer 2

electron spin

Question 3

As a rule, the ______ unpaired electrons per atom a substance has, the more magnetic the substance will be

Answer 3

more

Question 4

a group of aligned atoms having a single magnetic field

Answer 4

domain

Question 5

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

Answer 5

domain theory

Question 6

describes substances that have no unpaired electrons and are always slightly repelled by either pole of a magnet

Answer 6

diamagnetic

Question 7

describes substances that have only one unpaired electron and are weakly attracted to magnets

Answer 7

paramagnetic

Question 8

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

Answer 8

ferromagnetic

Question 9

describes substances that can be quickly magnetized even in a weak magnetic field

Answer 9

magnetically soft

Question 10

magnet made from magnetically soft material

Answer 10

temporary magnet

Question 11

describes materials whose domains strongly resist changes in the direction of their magnetic fields

Answer 11

magnetically hard

Question 12

magnet made from magnetically hard material

Answer 12

permanent magnet

Question 13

magnetizing by stroking an object with a magnet

Answer 13

magnetizing by contact

Question 14

magnetizing by contact is ______ (temporary or permanent)

Answer 14

temporary or permanent

Question 15

temporary magnetization caused by placing an object within a magnetic field

Answer 15

magnetizing by induction

Question 16

magnetizing caused around a wire by electricity flowing through a wire

Answer 16

magnetizing by electricity

Question 17

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

Answer 17

electromagnet

Question 18

the rule stating that if the thumb of the left hand is pointed along a wire (or other conductor) in the direction of electron current, the fingers encircle the conductor in the direction of the generated magnetic field

Answer 18

left-hand rule

Question 19

a magnetically soft material placed within the coils of an electromagnet in order to strengthen its field

Answer 19

core

Question 20

the temperature at which ferromagnetic material’s domains disappear

Answer 20

Curie point

Question 21

the resistance of a magnet to be demagnetized by a magnetic field

Answer 21

coercivity

Question 22

piece of magnetic material that you lay across the top of two magnets when they are stored

Answer 22

keeper

Question 23

force on an electric charge moving in a magnetic field that causes the charge to deviate from its original path

Answer 23

deflecting force

Question 24

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

Answer 24

magnetic compass

Question 25

a British pioneer of electrostatics and discovered that a compass points north because it is guided by earth’s magnetic field

Answer 25

William Gilbert

Question 26

the book in which William Gilbert published his findings on magnetism

Answer 26

De Magnete

Question 27

the deviation of a compass needle from true north

Answer 27

angle of declination

Question 28

a line connecting points of equal declination

Answer 28

isogonic line

Question 29

a line connecting all points where a compass needle points true north

Answer 29

agonic line

Question 30

(also called magnetic dip) the phenomenon in which a compass constructed with a magnet that swings vertically instead of horizontally points in the angle at which the lines of flux enter the earth

Answer 30

inclination

Question 31

a line connecting points of equal inclination

Answer 31

isoclinic line

Question 32

an isoclinic line where the angle of inclination is 0°

Answer 32

magnetic equator