Magnetic flux  in weber in a closed circuit of resistance  varies with time  as . The magnitude of induced current at  is

A conducting circular loop is placed in a uniform magnetic field,  with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of . The induced e.m.f. when the radius is , is

A coil of 50 turns is pulled in  between the poies of a magnet, where its area includes  to . The average e.m.f. is

A long solenoid having 200 turns per  carries a current of . At the centre of it is placed a coil of 100 turns of cross-sectional area  having its axis parallel to the field produced by the solenoid. When the direction of current in the solenoid is reversed within , the induced e.m.f. in the coil is

A 100 turns coil of area of cross section  having  resistance is held perpendicular to a magnetic field of . If it is removed from the magnetic field in one second, the induced charge produced in it is 

A thin circular ring of area  is held perpendicular to a uniform magnetic field of induction . A small cut is made in the ring and a galvanometer is connected across the ends such that the total resistance of the circuit is . When the ring is suddenly squeezed to zero area, the charge flowing through the galvanometer is   

A rectangular coil of 100 turns and size  is placed perpendicular to a magnetic field of . The induced e.m.f. when the field drops to  in  is

A rectangular coil of 20 turns and area of cross-section 25 sq.  has a resistance of . If a magnetic field which is perpendicular to the plane of coil changes at a rate of 1000 tesla per second, the current in the coil is

A horizontal telegraph wire  long running east and west in a part of a circuit whose resistance is . The wire falls to  and  weber/  then the current induced in the circuit is

A solenoid has 2000 turns wound over a length of . Its cross-sectional area is . Around its central section a coil of 300 turns is wound. If an initial current of 2 A flowing in the solenoid is reversed in , the emf induced in the coil will be