Question

A coil of wire of certain radius has 600 turns and a self inductance of 108 mH. The self inductance of a second similar coil of 500 turns will be

• A. 74 mH
• B. 75 mH
• C. 76 mH
• D. 77 mH

Answer 1

Answer: (B)

Inductance, L $\propto$ N${}^2$
$\therefore$ Inductance of similar coil of different turns is given by L' = L $\frac{N^{\prime 2}}{N^2}=108\times {\left(\frac{500}{6000}\right)}^2$ = 75 m H