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Question
A coil of inductance 5.0 mH and negligible resistance is connected to the oscillator of the previous problem. Find the peak currents in the circuit for ω = 100 s−1, 500 s−1, 1000 s−1.
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Solution
Given:
Inductance of the coil, `L = 5.0 mH = 0.005 H`
(a) At ω = 100 s−1:
Reactance of coil `(X_L)` is given by,
`X_L = omegaL`
Here, `omega`= angular frequency
`therefore X_L = 100xx0.005 = 0.5 Ω`
peak current , `l_0 = 10/0.5 = 20 A`
(b) At `omega = 500 s^-1`
Reactance, `X_L = 500 xx 5/1000`
= 2.5 Ω
peak current, `l_0 = 10/2.5 = 4A`\
(c) ω = 1000 s−1:
`Reactance, X_L = 1000 xx 0.005 = 5 Ω`
Peak current, `l_0 = 10/5 = 2A`
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