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The instantaneous values of alternating current and voltage in a circuit are given as
i=1/(√2)sin (100π t) ampere, e=1/(√2)sin (100π t+π/3) volt
The average power in watts consumed in the circuit is

Asked in NEET 2012 Mains · Average power and heating

Answer: (4) 1/8

Step-by-step solution

Read off the amplitudes and the phase difference:

i₀=e₀=1/(√2) and φ=π/3.

The rms values are iᵣₘₛ=eᵣₘₛ=(1/√2)/(√2)=1/2.

P=eᵣₘₛiᵣₘₛ cos φ=1/2×1/2×cos π/3 =1/2×1/2×1/2=1/8 W.

Why the other options are wrong

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