A cylindrical bar magnet is rotated about its axis (Fig ). A wire is connected from the axis and is made to touch the cylindrical surface through a contact. Then
Options:
(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=2π/ω.
(d) a time varying non-sinosoidal current flows through the ammeter A.