Question

Define and explain the following terms in case of a bar magnet:

i. Axis 

ii. Equator 

iii. Magnetic length

Answer 1

i. Axis: It is the line passing through both the poles of a bar magnet. There is only one axis for a given bar magnet.

ii. Equator:

• A line passing through the centre of a magnet and perpendicular to its axis is called magnetic equator.
• The plane containing all equators is called the equatorial plane.
• The locus of points, on the equatorial plane, which are equidistant from the centre of the magnet is called the equatorial circle.
• The popularly known ‘equator’ of the planet is actually an ‘equatorial circle’. Such a circle with any diameter is an equator.

iii. Magnetic length (2l)

It is the distance between the two poles of a magnet.

Magnetic length (2l) = \(\frac{5}{6}\) × Geometric length.