The electric current in AC circuit is given by the relation i-3 sinωt+4 cosωt. The rms value of the current in the circuit in ampere is

Options

(a) 5/√2
(b) 5√2
(c) √2/5
(d) 1/√2

Correct Answer:

5/√2

Explanation:

The current through the AC circuit is given by

i = 3 sin ωt + 4 cos ωt

The maximum value of current is

I(max) = √(3² + 4v) = √25 = 5 unit

The rms value of current, I(rms) = I(max) / √2 = (5 / √2) unit