Question

A cylindrical bar magnet is rotated about its axis as shown in the figure. A wire is connected from the axis and is made to touch the cylindrical surface through a contact. Then

• A. A direct current flows in the Ammeter $A$
• B. No current flows through the ammeter $A$
• C. An alternating sinusoidal current flows through the ammeter A with a time period , $T=\frac{2\pi }{\omega }$
• D. A time varying non-sinusoidal current flows through the ammeter $A$

Answer 1

The correct option is B No current flows through the ammeter $A$

As there is no change in magnetic flux associated with the circuit, no current is induced in the circuit. The ammeter A shows no deflection.