A coil with an average diameter of 0.02 m is placed perpendicular to a magnetic field of 6000 T. If the induced e.m.f. is 11 V when magnetic field is changed to 1000 T in 4 s, what is the number of turns in the coil ?

Explanation

To solve the problem step by step, we will use the formula for induced electromotive force (e.m.f.) in a coil due to a change in magnetic flux.

### Step 1: Understanding the given values
We are given:
- Diameter of the coil, \(d = 0.02 \, m\)
- Initial magnetic field, \(B_1 = 6000 \, T\)
- Final magnetic field, \(B_2 = 1000 \, T\)
- Time interval, \(\Delta t = 4 \, s\)
...