A solenoid of $N = 200$ turns, length $L = 20$ cm and cross-section $A…

Question

A solenoid of $N = 200$ turns, length $L = 20$ cm and cross-section $A = 5\ 	ext{cm}^2$ has self-inductance approximately:

Accepted Answer

A. 126 μH

$L = \mu_0 N^2 A/L$. Substituting: $L = (4\pi 	imes 10^{-7})(200)^2 (5	imes10^{-4})/(20	imes10^{-2}) = (4\pi 	imes 10^{-7})(40000)(5	imes10^{-4})/0.2 = 1.26 	imes 10^{-4}$ H $\approx 126\ \mu$H (or equivalently 0.126 mH).

Answer

1.26 μH

Answer

1.26 mH

Answer

12.6 μH

A solenoid of $N = 200$ turns, length $L = 20$ cm and cross-section $A = 5\ \text{cm}^2$ has self-inductance approximately: