A large circular coil of radius R and a small circular coil of radius r are put in vicinity of each other. If coefficient of mutual inductance of this pair equals 1 mH, what would be the flux linked with larger coil when a current of 0.5 A flows through the smaller coil? When would current in the smaller coil falls to zero, what would be its effect in the larger coil ?

Explanation

To solve the problem step by step, we will follow these steps:

### Step 1: Understand the Given Information
- We have a large circular coil with radius \( R \) and a small circular coil with radius \( r \).
- The coefficient of mutual inductance \( M \) between the two coils is given as \( 1 \, \text{mH} = 1 \times 10^{-3} \, \text{H} \).
- A current \( I_s = 0.5 \, \text{A} \) flows through the smaller coil.

### Step 2: Calculate the Flux Linked with the Larger Coil
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