Which term refers to the effective heating value of an alternating current waveform compared to direct current?

Which term refers to the effective heating value of an alternating current waveform compared to direct current?

• A. Capacitance
• B. Effective Value
• C. Inductance
• D. Peak Voltage

Answer: (B)

The key idea is that the heating effect of an AC waveform is described by its effective value, which is the RMS (root-mean-square) value. This is the DC-equivalent value that would produce the same average power in a resistor as the AC waveform does. The RMS value is defined by averaging the square of the voltage or current over time: V_rms = sqrt( (1/T) ∫ v(t)^2 dt ). For a sine wave, V_rms equals the peak voltage divided by sqrt(2), and similarly I_rms equals the peak current divided by sqrt(2). Since power in a resistor is P = V_rms^2 / R = I_rms^2 R, the RMS value directly reflects the heating effect of the waveform. Capacitance and Inductance describe how circuits store and release energy and influence impedance, not the heating value. Peak Voltage is the maximum instantaneous value, which does not represent the average heating effect. Thus the term that best describes the effective heating value of an AC waveform compared to DC is the Effective Value.

The key idea is that the heating effect of an AC waveform is described by its effective value, which is the RMS (root-mean-square) value. This is the DC-equivalent value that would produce the same average power in a resistor as the AC waveform does. The RMS value is defined by averaging the square of the voltage or current over time: V_rms = sqrt( (1/T) ∫ v(t)^2 dt ). For a sine wave, V_rms equals the peak voltage divided by sqrt(2), and similarly I_rms equals the peak current divided by sqrt(2). Since power in a resistor is P = V_rms^2 / R = I_rms^2 R, the RMS value directly reflects the heating effect of the waveform.

Capacitance and Inductance describe how circuits store and release energy and influence impedance, not the heating value. Peak Voltage is the maximum instantaneous value, which does not represent the average heating effect. Thus the term that best describes the effective heating value of an AC waveform compared to DC is the Effective Value.