A coil of radius R carries current `i_1`. Another concentric coil of radius `r(rlt ltR)` carries current `i_2`. Planes of two coils are mutually perpendicular and both the coil are free to rotate about common diametre. Find maximum kinetic energy of smaller coil when both the coils are released, masses of coils are M and m, respectively.

Explanation

To find the maximum kinetic energy of the smaller coil when both coils are released, we can follow these steps:

### Step 1: Understand the System
We have two concentric coils:
- A larger coil of radius \( R \) carrying current \( i_1 \) and mass \( M \).
- A smaller coil of radius \( r \) (where \( r < R \)) carrying current \( i_2 \) and mass \( m \).
- The planes of the coils are mutually perpendicular, and they can rotate about a common diameter.

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