Question

A circular coil of 500 turns of a wire has an enclosed area of 0.1 m² 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 sec. How much charge will pass when the coil is connected to a galvanometer with a combined resistance of 50 ohms

• A. 0.2 C
• B. 0.4 C
• C. 2 C
• D. 4 C

Answer 1

Answer: (B)

0.4 C

Answer 2

Given N = 500, A = 0.1 m², θ₁ = 0^o, θ₂ = 180^o, B = 0.2 T,

∆t = 0.1 sec, R = 50Ω

By using $q = \frac { N } { R } \cdot d \phi = - \frac { N } { R } B A \left( \cos \theta _ { 2 } - \cos \theta _ { 1 } \right)$;

$q = 0.4 C$ .