Question

When a sinusoidal voltage E = 200 sin 314 t is applied to a resistor of 10 Ω resistance, the power dissipated is 250 Watts.

(a) True

(b) False

I had been asked this question by my college director while I was bunking the class.

This intriguing question originated from AC Voltage Applied to a Resistor in division Alternating Current of Physics – Class 12

Answer 1

Right answer is (a) True

Easy explanation: Yes, this is a true statement. The explanation is given as follows:

E = E0 sinωt.

Erms = \(\frac {E_0}{\sqrt {2}} = \frac {50}{\sqrt {2}}\)

Erms = 35.35 V.

Irms = \(\frac {E_{rms}}{R} \, = \, \frac {35.5}{5} \)

Irms = 7.07 A.

Power dissipated = Ev × Iv = 35.35 × 7.07

Power dissipated = 249.92 W ≈ 250 W.