Magnetism and M...

The radius of the coil of a tangent galvanometer which has 10 turns is 0.1 m. The current required to produce a deflection of 60° (B_H = 4 × 10^–5T) is

A magnet oscillating in a horizontal plane has a time period of 2 second at a place where the angle of dip is 30° and 3 seconds at another place where the angle of dip is 60°. The ratio of resultant magnetic fields at the two places is

A magnetic needle is made to vibrate in uniform field H, then its time period is T. It is vibrates in the field of intensity 4H, its time period will be

Two bar magnets of the same mass, length and breadth but magnetic moments M and 2M respectively, when placed in same position, have time period 3 sec. What will be the time period when they are placed in different position.

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

A magnet is suspended in such a way that it oscillates in the horizontal plane. It makes 20 oscillations per minute at a place where dip angle is 30° and 15 oscillations per minute at a place where dip angle is 60°. The ratio of total earth\'s magnetic field at the two places is

A bar magnet is oscillating in the earth\'s magnetic field with time period T. If its mass is increased four items then its time period will be

Two magnets A and B are identical in mass, length and breadth but has different magnetic moments. In a vibration magnetometer, if the time period of B is twice the time period of A. The ratio of the magnetic moments M_A/M_B of the magnets will be

A magnet of magnetic moment M oscillating freely in earth\'s horizontal magnetic field makes n oscillations per minute. If the magnetic moment is quadrupled and the earth\'s field is doubled, the number of oscillations made per minute would be

A magnetic needle suspended horizontally by an unspun silk fibre, oscillates in the horizontal plane because of the restoring force originating mainly from