A bar magnet of length $14 \,cm$ is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A neutral point is obtained at a distance of $18\, cm$ from the center of the magnet. If $B _{ H }=0.4 \,G ,$ the magnetic moment of the magnet is $\left(1\, G =10^{-4} T \right)$
$2.880 \times 10^{3}\, J \,T ^{-1}$
$2.880 \times 10^{2}\, J\, T ^{-1}$
$2.880\, J\, T ^{-1}$
$28.80\, J\, T ^{-1}$
Magnetic meridian is a
Which of the following relation is correct in magnetism
Two normal uniform magnetic field contain a magnetic needle making an angle $60°$ with $F$. Then the ratio of $\frac{F}{H}$ is
The lines of forces due to earth's horizontal component of magnetic field are
A magnetic compass needle oscillates $30$ times per minute at a place where the dip is $45^o$, and $40$ times per minute where the dip is $30^o$. If $B_1$ and $B_2$ are respectively the total magnetic field due to the earth at the two places, then the ratio $B_1/B_2$ is best given by