Given below are two statements:
Statement I : An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor.
Statement II : An AC circuit containing a pure capacitor or a pure inductor consumes high power due to its non-zero power factor.
In the light of above statements, choose the correct answer from the options given below :

Question

Why can high or very low resistance not be measured accurately using the Wheatstone bridge principle?

Answer 1

Let's analyze each statement to determine their validity:

Statement I: An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor.

For electrical resonance to occur in an AC circuit, there must be both a capacitor and an inductor present. Resonance typically occurs in an LC circuit (a circuit containing both an Inductor 'L' and a Capacitor 'C') at a specific frequency called the resonant frequency. At this frequency, the inductive reactance and capacitive reactance are equal in magnitude but opposite in phase, canceling each other out, and the circuit impedance becomes purely resistive. Therefore, an AC circuit cannot undergo electrical resonance if it contains only a capacitor or only an inductor. Thus, Statement I is false.

Statement II: An AC circuit containing a pure capacitor or a pure inductor consumes high power due to its non-zero power factor.

In an AC circuit with only a pure capacitor or a pure inductor, the power factor is zero. This is because the current either leads or lags the voltage by 90 degrees, meaning that there is no real power consumed in the circuit even though reactive power is present. Such circuits store energy temporarily and return it back to the source per cycle without actual energy consumption. Therefore, Statement II is also false because such a circuit neither consumes real power nor has a non-zero power factor.

Based on the analysis of both statements, we conclude that:

Statement I is false because an AC circuit needs both a capacitor and an inductor to undergo electrical resonance.
Statement II is false because a pure capacitor or inductor does not consume real power due to its zero power factor.

Conclusion: The correct answer is: Both Statement I and Statement II are false.

Answer 2

Let's analyze each statement to determine their validity:

Statement I: An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor.

For electrical resonance to occur in an AC circuit, there must be both a capacitor and an inductor present. Resonance typically occurs in an LC circuit (a circuit containing both an Inductor 'L' and a Capacitor 'C') at a specific frequency called the resonant frequency. At this frequency, the inductive reactance and capacitive reactance are equal in magnitude but opposite in phase, canceling each other out, and the circuit impedance becomes purely resistive. Therefore, an AC circuit cannot undergo electrical resonance if it contains only a capacitor or only an inductor. Thus, Statement I is false.

Statement II: An AC circuit containing a pure capacitor or a pure inductor consumes high power due to its non-zero power factor.

In an AC circuit with only a pure capacitor or a pure inductor, the power factor is zero. This is because the current either leads or lags the voltage by 90 degrees, meaning that there is no real power consumed in the circuit even though reactive power is present. Such circuits store energy temporarily and return it back to the source per cycle without actual energy consumption. Therefore, Statement II is also false because such a circuit neither consumes real power nor has a non-zero power factor.

Based on the analysis of both statements, we conclude that:

Statement I is false because an AC circuit needs both a capacitor and an inductor to undergo electrical resonance.
Statement II is false because a pure capacitor or inductor does not consume real power due to its zero power factor.

Conclusion: The correct answer is: Both Statement I and Statement II are false.

The Correct Option is B

Solution and Explanation

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