Question Detail
Question
The power dissipated by a 72 Ω resistor connected to a sinusoidal a.c. source is 24W. Determine the peak-to-peak voltage across the resistor.
Correct Answer
Option A is the correct answer.
Detailed Explanation
Given: Power (P) = 24W, Resistance (R) = 72 Ω.Power in an AC circuit is P = Vrms2 / R.Vrms2 = P * R = 24W * 72 Ω = 1728 V2.Vrms = √1728 ≈ 41.569 V.The peak voltage Vpeak = Vrms * √2 = 41.569 V * 1.414 ≈ 58.77 V.The peak-to-peak voltage Vp-p = 2 * Vpeak = 2 * 58.77 V ≈ 117.54 V.
Hint
First calculate the RMS voltage, then the peak voltage, and finally the peak-to-peak voltage.