Two concentric circular coils of radius `r` and `R` are placed coaxially with centres coinciding If `R gt gt r` then calculate the mutual inductance the coils.

Explanation

To calculate the mutual inductance between two concentric circular coils with radii \( r \) (small coil) and \( R \) (large coil), where \( R \gg r \), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have two coils: a smaller coil with radius \( r \) and a larger coil with radius \( R \).
- The coils are coaxially placed, meaning they share the same center.

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