Question

The self-inductance of a solenoid of 600 turns is 108 mH. The self-inductance of a coil having 500 turns with the same length, the same radius and the same medium will be ______.

Options

• 95 mH

• 90 mH

• 85 mH

• 75 mH

Answer 1

The self-inductance of a solenoid of 600 turns is 108 mH. The self-inductance of a coil having 500 turns with the same length, the same radius and the same medium will be 75 mH.

Explanation:

`L = (mu_0 N^2 A)/l`

So, L ∝ N²

∴ `L_1/L_2 = N_1^2/N_2^2`

Or, `108/L_2 = 600^2/500^2`

∴ `L_2 = 108 xx 25/36`

= 75 mH