5.14. If the bar magnet in exercise 5.13 is turned around by , where will the new null points be located?
Given, d = 14 cm
The magnetic field at a distance d from the centre of the magnet on its axis:
If the bar magnet is turned through 180°, then the neutral point will lie on the equatorial (perpendicular bisector) line.
The magnetic field at a distance d' from the centre of the magnet on the normal bisector is:
Equating these two, we get:
d' = 14 x 0.794 = 11.1cm
The new null points will be at a distance of 11.1 cm on the normal bisector.