The Total solution for NCERT class 6-12
A short bar magnetplaced in a horizontal plane has its axis aligned┬аalong the magneticnorth-south direction. Null points are found on the axis of the magnet at 14 cmfrom the centre of the magnet. The earthтАЩs magnetic field at the place is 0.36G and the angle of dip is zero. What is the total magnetic field on the normalbisector of the magnet at the same distance as the nullтИТpoint (i.e., 14 cm)from the centre of the magnet? (At┬аnull points, field due to amagnet is equal and opposite to the horizontal component of earthтАЩs magneticfield.)
EarthтАЩs magnetic fieldat the given place,┬аH┬а= 0.36 G
Where,
= Permeability of freespace
M┬а= Magnetic moment
The magnetic field atthe same distance┬аd, on the equatorial line of the magnet is givenas:
Total magnetic field,
Hence, the magneticfield is 0.54 G in the direction of earthтАЩs magnetic field.