The time period of a vibration magnetometer is $T_0$. Its magnet is replaced by another magnet whose moment of inertia is $3$ times and magnetic moment is $1/3$ of the initial magnet. The time period now will be

Two short magnets having magnetic moments in the ratio $27 : 8,$  when placed on opposite sides of a deflection magnetometer, produce no deflection. If the distance of the weaker magnet is $0.12$ $m$ from the centre of deflection magnetometer, the distance of the stronger magnet from the centre is.......$m$

When $\sqrt 3 $ $ampere$ current is passed in a tangent galvanometer, there is a deflection of $ 30° $ in it. The deflection obtained when $3$ $ampere$ current is passed, is.....$^o$

Two magnets are held together in a vibration magnetometer and are allowed to oscillate in the earth’s magnetic field. With like poles of magnets together, $12\, oscillations$ per minute are made but for unlike poles together only $4\, oscillations$ per minute are executed. The ratio of their magnetic moments is

The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is $2 \,s. $ The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together. The time period of this combination will be

If a brass bar is placed on a vibrating magnet, then its time period