Question

A voltage V = V₀ sin ωt is applied to a series LCR circuit. Derive the expression for the average power dissipate over a cycle. 

Under what conditions is (i) no power dissipated even though the current flows through the circuit, (ii) maximum power dissipated in the circuit ?

Answer 1

Conditions :

(i) No power is dissipated when R = 0 (or ϕ = 90°)

[Note : Also accepts if the student writes 'This condition cannot be satisfied for a series LCR circuit'.]

(ii) Maximum power is dissipated when X_L = X_C.

Or