Motional Emf

A rectangular, a square, a circular, and an elliptical loop, all in the plane, are moving out of a uniform magnetic field with a constant velocity, The magnetic field is directed along the negative axis direction. The induced emf, during the passage of these loops out of the field region, will not remain constant for:

1.	the rectangular, circular, and elliptical loops.
2.	the circular and the elliptical loops.
3.	only the elliptical loop.
4.	any of the four loops.

The figure shows a circuit that contains three identical resistors with resistance $$ each, two identical inductors with inductance each, and an ideal battery with emf . The current through the battery just after the switch is closed will be:
  
1.
2.
3.
4.

A wheel with metallic spokes, each m long, is rotated with a speed of rpm in a plane perpendicular to a magnetic field of . The induced emf between the axle and rim of the wheel will be:

1. V
2. V
3. V
4. V