A solenoidal coil has `50` turns per centimetre along its length and a cross-sectional area of `4 xx 10^(-4) m^(2)`. `200` turns of another wire is wound round the first solenoid co-axially. The two coils are electrically insulated from each other. Calculate the mutual inductance between the two coils.

Explanation

`n_(1) = 50` turns per `cm`, `= 5000` turns per metre
`n_(2)l = 200, A = 4 xx 10^(-4) m^(2) , M = mu_(0)n_(1)(n_(2)l)A`
`= 4pi xx 10^(-7) xx 5000 xx 200 xx 4 xx 10^(-4)H = 5.03 xx 10^(-4)H`