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Question
Which of the following plots may represent the reactance of a series LC combination?
Solution
(d)
The reactance of a series LC circuit is given by,
`X = X_L - X_c = omegaL - 1/"omegaC"`
⇒ `X =2pi fL - 1/(2pifC) `
The correct relation between the reactance and f is represented by the graph in option (d).
`X = 0, "when" X_L = X_c`
Thus plot d represent the reactance of a series LC combination.
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