A circular coil of radius $0.8\;cm$ and $20 \;turns$ is rotated about its vertical diameter with an angular speed of $50\; rad/s$ in a uniform horizontal magnetic field of magnetic $3.0 \times 10^-{2} T.$ Obtain the maximum and average $emf$ induced in the coil. If the coil forms a closed -loop of resistance $10 \Omega$, where does the power come from ?
