Question 14

If the bar magnet in exercise 5.13 is turned around by 180º, wherewill the new null points be located?

Answer

The magnetic field on the axis of the magnet at a distance *d*_{1}= 14 cm, can be written as:

Where, *M* = Magnetic moment

*μ _{0}*= Permeability of free space

*H*= Horizontal component of the magnetic field at *d*_{1}

If the bar magnet is turned through 180°, then the neutral point will lie on the equatorial line.

Hence, the magnetic field at a distance *d*_{2}, on the equatorial line of the magnet can be written as:

Equating equations (1) and (2), we get:

The new null points will be located 11.1 cm on the normal bisector.

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