B-H Hysteresis Loop — Practice Quiz

Question 1

Area enclosed by the B-H hysteresis loop equals:

Accepted Answer

Energy loss per unit volume per cycle

Answer

Net magnetic moment

Answer

Saturation field

Answer

Remanence

Question 2

Coercivity H_c is:

Accepted Answer

Reverse field needed to reduce B to zero

Answer

Saturation magnetization

Answer

Field at which B reaches B_s

Answer

Permeability at low H

Question 3

Soft magnetic materials have:

Accepted Answer

Narrow loop, low energy loss, used in transformers

Answer

Large loop area, used as permanent magnets

Answer

Zero hysteresis

Answer

Same as hard materials

Question 4

When iron is heated above its Curie temperature, hysteresis loop:

Accepted Answer

Vanishes (material becomes paramagnetic)

Answer

Widens

Answer

Remains the same

Answer

Becomes square

Question 5

Permanent magnets are made of:

Accepted Answer

Hard magnetic materials (high coercivity)

Answer

Soft magnetic materials (low coercivity)

Answer

Paramagnetic materials

Answer

Diamagnetic materials