Question

A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of $50{\text{rad/s}}^{-1}$ in a uniform horizontal magnetic field of $3.0\times {10}^{-2}\text{T}$. The maximum emf induced in the coil will be ___ $\times {10}^{-2}\text{volt}$ (rounded off to the nearest integer).

• A. 6
• B. 6.0
• C. 6.00

Answer 1

Answer: (A), (B), (C)

Given,

Radius, $r=8\times {10}^{-2}\text{m}$

$N=20,B=3\times {10}^{-2}\text{T}$

$\omega =50\text{rad/s}$

Area$\left(A\right)=\pi r^2=\pi \times (0.08{)}^2$

The maximum induced emf is given by,

$E_{max}=BAN\omega$

$E_{max}=3\times {10}^{-2}\times \pi \times (0.08{)}^2\times 20\times 50\text{Volt}$

$E_{max}=6.02\times {10}^{-2}\text{Volt}$

Hence, $n=6$