Question Detail
Question
A resistor, 100Ω, is connected to an a.c. source ν = 350 sin ωt. If ω = 1256 rad/s, find the r.m.s current and instantaneous current at time 0.30s respectively.
Correct Answer
Option D is the correct answer.
Detailed Explanation
V_peak = 350V. I_rms = V_peak/(√2 × R) = 350/(1.414×100) = 2.47A. i(t) = (350/100) sin(1256×0.30) = 3.5 sin(376.8 rad) ≈ 3.5×0.287 = 1.01A.
Hint
Calculate RMS current using V_peak/(√2 R) and instantaneous current using V_peak/R sinωt.