Magnetic field intensity is defined as
Magnetic moment per unit volume
Magnetic induction force acting on a unit magnetic pole
Number of lines of force crossing per unit area
Number of lines of force crossing per unit volume
A bar magnet of length $ 3 \,cm$ has points $A $ and $ B$ along its axis at distances of $24\, cm$ and $48\, cm$ on the opposite sides. Ratio of magnetic fields at these points will be
A short bar magnet of magnetic movement $5.25 \times 10^{-2} \;J\, T ^{-1}$ is placed with its axis perpendicular to the earth's field direction. At what distance from the centre of the magnet, the resultant field is inclined at $45^{\circ}$ with earth's field on
$(a)$ its normal bisector and
$(b)$ its axis.
Magnitude of the earth's field at the place is given to be $0.42 \;G$. Ignore the length of the magnet in comparison to the distances involved.
The magnetic moment of a magnet of length $10\, cm$ and pole strength $ 4.0\, Am$ will be......$A{m^2}$
Force between two unit pole strength placed at a distance of one metre is
A bar magnet of length $10 \,cm$ and having the pole strength equal to $10^{-3}$ weber is kept in a magnetic field having magnetic induction $ (B)$ equal to $4\pi \times {10^{ - 3}}$ Tesla. It makes an angle of $30°$ with the direction of magnetic induction. The value of the torque acting on the magnet is