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Question
A 100 μF capacitor is charged with a 50 V source supply. Then source supply is removed and the capacitor is connected across an inductance, as a result of which 5A current flows through the inductance. Calculate the value of the inductance.
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Solution
Here, C = 100 μF = 100 × 10−6 F = 10−4 F
V = 50 volt, i = 5A, L = ?
The energy stored in the electric field in the capacitor = `1/2"CV"^2`
The energy stored in the magnetic field in the inductor = `1/2"Li"^2`
As energy stored in inductor = energy stored in capacitor,
∴ `1/2"CV"^2 = 1/2"Li"^2`
∴ L = `"C" "V"^2/"i"^2`
∴ L = C`("V"/"i")^2`
`= 10^-4(50/5)^2 = 10^-4 xx 10^2 = 10^-2 "H"`
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