# A circular coil of 500 turns of wire has an enclosed area of 0.1 m^2 per turn. It is kept perpendicular to a magnetic field…

Q: A circular coil of 500 turns of wire has an enclosed area of 0.1 m^2 per turn. It is kept perpendicular to a magnetic field of induction 0.2 T and rotated by 180^o about a diameter perpendicular to the field in 0.1 s. How much charge will pass when the coil is connected to a galvanometer with a combined resistance of 50 Ω.

Sol: $\large q = \frac{\phi_1 – \phi_f}{R}$

$\large q = \frac{NBA – (-NBA)}{R} = \frac{2 N B A}{R}$

$\large = \frac{2\times 500 \times 0.2 \times 0.1}{50}$

q = 0.4 c