Question

A rectangular coil of $300$ turns has an average area of $25\, cm \times 10\, cm .$ The coil rotates with a speed of $50\, cps$ in a uniform magnetic field of strength $4 \times 10^{-2} T$ about an axis perpendicular to the field. The peak value of the induced emf is (in volt)

• A. $3\, \pi$
• B. $30\, \pi$
• C. $300\, \pi$
• D. $3000\, \pi$

Answer 1

Answer: (B)

$30\, \pi$

Answer 2

E = $n$BA $\omega$ sin $\theta$ = $300 \times 4 \times 10^{-2} \times 25 \times 10 \times 10^{-4} \times 2 \pi \times 50 = 30 \pi \, V. \,(sin 90^{\circ} = 1)$