Through a long solenoid of diameter `4.1` cm, having 100 turns per cm, a current I = 1A is flowing. At its centre, a 60 turns closely packed coil of diameter `3.1` cm si placed such that the coil is coaxial with the long solenoid. The current in the solenoid is reduced to zero at a steady rate in 10 ms. What is the magnitude of emf induced in the coil while the current in the solenoid is changing?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Identify the Given Data
- Diameter of the solenoid, \( D_s = 4.1 \, \text{cm} = 0.041 \, \text{m} \)
- Turns per unit length of the solenoid, \( n_s = 100 \, \text{turns/cm} = 10000 \, \text{turns/m} \)
- Current in the solenoid, \( I = 1 \, \text{A} \)
- Number of turns in the coil, \( N_c = 60 \)
- Diameter of the coil, \( D_c = 3.1 \, \text{cm} = 0.031 \, \text{m} \)
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