The unit of reduction factor of tangent galvanometer is

Twists of suspension fibre should be removed in vibration magnetometer so that

The magnet of a vibration magnetometer is heated so as to reduce its magnetic moment by $19\%$. By doing this the periodic time of the magnetometer will

A tangent galvanometer has $80$ turns of wire. The internal and external diameters of the coil are $19 \,cm$ and $21 \,cm$ respectively. The reduction factor of the galvanometer at a place where $H=0.32$ oersted will be $(1$ oersted $=80 \,A / m )$

A tangent galvanometer has a coil with $50$ $turns$ and radius equal to $4$ $cm$. A current of $0.1 $ $A$ is passing through it. The plane of the coil is set parallel to the earth's magnetic meridian. If the value of the earth's horizontal component of the magnetic field is $7 \times {10^{ - 5}}$ $tesla$ and  ${\mu _0} = 4\pi \times {10^{ - 7}}\, weber/amp \times m$, then the deflection in the galvanometer needle will be.....$^o$

A long vertical wire in which a current is flowing produces a neutral point with the earth's magnetic field at a distance of $5\, cm$ from the wire. If the horizontal component of the earth's magnetic induction is $0.18\, gauss$, then the curent in the wire is......$A$