### JEE Main On 16 April 2018 Question 11

##### Question: A coil of cross-sectional area A having n turns is placed in a uniform magnetic field B. When it is rotated with an angular velocity $ \omega , $ the maximum e.m.f. induced in the coil will be [JEE Main 16-4-2018]

#### Options:

A) $ nBA\omega $

B) $ \frac{3}{2}nBA\omega $

C) $ 3nBA\omega $

D) $ \frac{1}{2}nBA\omega $

## Show Answer

#### Answer:

Correct Answer: A

#### Solution:

Given, a coil of N turns an area A, rotated with angular speed $ \omega $ in a uniform magnetic field B.

The flux linking to the coil, sin $ \phi =NBA\sin (\omega t) $

Therefore, Induced $ E=d(NBA\sin (\omega t)/dt) $

E= NBA Emax= NBA