chapter 2

Question 1

Magnetic domains

Answer 1

Small groups of magnetic atoms that tend to form tiny permanent magnets. When the domains are arranged in a random pattern, the metal is nonmagnetized. A magnetized metal is one whose domains are all aligned in the same direction.

Question 2

Flux lines

Answer 2

A collective designation for all electric or magnetic lines of force in a region. Electric flux lines extend in all directions from a charged particle. Magnetic flux lines extend from the magnetic poles.

Question 3

Electromagnetism

Answer 3

Magnetism that results from the flow of electric current through a wire or coil of wire.

Question 4

Magnet

Answer 4

An object that has the ability and property to attract or repel magnetic materials.

Question 5

Magnetic field

Answer 5

A region around a permanent magnet, or around a current-carrying conductor or coil of wire, in which magnetic forces exist.

Question 6

Left-hand rule for electromagnetism in a wire

Answer 6

When you wrap the fingers of your left hand around the wire with your thumb pointing in the direction of current flow, your fingers will wrap in the direction of the magnetic field.

Question 7

Magnetomotive force (mmf)

Answer 7

The force that produces a magnetic field. This force results from a current flowing through a coil of wire. The strength of the generated mmf is determined by multiplying the amount of current (in amperes) by the number of turns in the coil.

Question 8

Ampere-turns

Answer 8

The unit of measurement of the magnetomotive force (mmf) in a coil of wire. The ampere-turns value is determined by multiplying the electric current (in amperes) flowing through the coil by the number of turns in the coil.