Permanent magnetism Questions

A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It:

A vibration magnetometer placed in magnetic meridian has a small bar magnet. The magnet executes oscillations with a time period of 2 sec in earth′s horizontal magentic field of 24 microtesla A ...

Alternating current can not be measured by D.C. ammeter because

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 t...

A magnetic needle lying parallel to a magnetic field requires W units of work to turn it through 60°. The torque needed to maintain the needle in this position will be

What should be amount of current through the ring of radius of 5 cm so that field at the centre equal to the eatrh′s magnetic field of 7 × 10-5 Wb/m2, is...

The earth′s magnetic field at a given point is 0.5 × 10-5 Wb m-2. this field is to be annulled by magnetic induction at the centre of a circular conducting loop of radius 5.0 cm. The curren...

Which is incorrect -