Q 12-06-012NEETJEE MainEasy
A coil of $100$ turns and area $0.02\ \text{m}^2$ lies perpendicular to a magnetic field that falls uniformly from $0.5$ T to zero in $0.1$ s. The average induced emf is
Answer: (B) $10$ V
Concept. Average emf $= N\dfrac{\Delta\phi}{\Delta t}$.
Step 1. Substitute.
$$\varepsilon = 100 \times \frac{0.02 \times 0.5}{0.1} = 10\ \text{V}$$
Answer. $10$ V (Option B).
Solution by Sreeraj P, M.Sc Physics