In pure capacitor circuit, which quantity is lagging

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Examoogle · Accepted Answer

Voltage

Explanation: In a pure capacitor circuit, the voltage across the capacitor lags the current through it by 90 degrees. This is due to the nature of how capacitors store and release energy. Working Principle: As the current changes, the capacitor takes time to charge and discharge, causing the voltage to respond with a delay. This results in the phase difference where voltage lags the current. Key Formulas: $I = C \frac{dV}{dt}$ — describes the relationship between current (I), capacitance (C), and the rate of change of voltage (V).; $V = \frac{1}{j \omega C} I$ — represents the voltage across a capacitor in phasor form, showing the lagging nature of voltage with respect to current. Key Points: In AC circuits, the current leads the voltage in capacitive circuits.; The phase difference of 90 degrees is characteristic of pure capacitive behavior. Advantages: Capacitors can improve power factor in circuits; They can be used for filtering applications. Disadvantages: Capacitors can introduce phase shift issues; They may have dielectric losses that affect performance. Applications: Power factor correction in electrical systems; Energy storage in power electronics. Additional Info: Standard Values: Capacitance values are usually provided in microfarads (µF) for common applications.. Wrong Options Explained: Option A = Current does not lag in a pure capacitor circuit; Option C = Only voltage lags, not both. Answer: B is correct — In a pure capacitor circuit, the voltage lags the current due to the inherent behavior of capacitive reactance. Exam Tip: Remember that in inductors, the current lags the voltage, while in capacitors, the voltage lags the current.

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