Question

The current waveform \(i(t)\) in a pure resistor of 20 \( \Omega \) is as shown in the figure below, then the power dissipated in the resistor is

• A. 135W
• B. 540W
• C. 270W
• D. 14.58W

Hint:

When calculating power dissipated in resistors, always use the RMS value of the current in the formula \( P = I_{\text{rms}}^2 R \).

Answer 1

The Correct Option is B

The power dissipated in the resistor is calculated using the formula: \[ P = I_{\text{rms}}^2 R \] Where \( I_{\text{rms}} \) is the RMS value of the current and \( R \) is the resistance. By analyzing the current waveform, we find the RMS value of the current \( I_{\text{rms}} = 9A \). Using \( R = 20 \, \Omega \), the power is: \[ P = (9)^2 \times 20 = 540W \] Thus, the correct answer is option (2).