Dependence on Area and Orientation

Q. The coil of area 0.1 $m^2$ has 500 turns. After placing the coil in a magnetic field of strength $4\times {10}^{-4}Wb/m^2$, if rotated through ${90}^{\circ }$ in 0.1 s, the average emf induced in the coil is

1. 0.012 V
2. 0.05 V
3. 0.1 V
4. 0.2 V

Q.

A coil of area $80$$c{m}^2$ and 50 turns is rotating with 2000 revolutions per minute about an axis perpendicular to a magnetic field of $0.05$ $Tesla$. The maximum value of the e.m.f. induced in it is

1. 

2. 

3. 

4.