Question

The presence of magnetic field at a point can be detected by means of:

(a) a strong magnet

(b) a solenoid

(c) a compass needle

(d) a current carrying wire.

Answer 1

The presence of magnetic field at a point can be detected by a compass needle. In the presence of a magnetic field, the needle of compass rests only in the direction of magnetic field and in the absence of any magnetic field, the needle of the compass can rest in any direction. So, the correct choice is (c).