Question

When an alternating emf e = 310 sin (100 πt)V is applied to a series LCR circuit, current flowing through it is i = 5 sin(100 πt + π/3)A.

1. What is the phase difference between the current and the emf?
2. Calculate the average power consumed by the circuit.

Answer 1

Given: e = 310 sin (100 πt)V

i = 5 sin(100 πt + π/3)A

1. Phase difference between i and e, Φ = π/3    ...[current leads by a phase difference π/3]

2. Average power consumed,

P_avg = `1/2 V_0I_0 cos Phi`

= `1/2 xx 310 xx 5xx cos pi//3`

= `(310 xx 5)/4`

= 387.5 W