Question

A circular loop placed in a plane perpendicular to the plane of paper carries a current when the key is ON. The current as seen from points A and B (in the plane of the paper and on the axis of the coil) is anticlockwise and clockwise respectively. The magnetic field lines point from B to A. The N-pole of the resultant magnet is on the face close to:

• A. A
• B. B
• C. A if the current is small, and B if the current is large
• D. B if the current is small, and A if the current is large

Answer 1

The correct option is A

A

Since the magnetic field lines point form B to A, it implies that they enter into B and emerge out of A.Clearly, the face close to A is the N-pole as field lines emerge out of north pole and enter into south pole.