Question

When a capacitor is connected in series LR circuit, the alternating current flowing in the circuit

• A. increases
• B. decreases
• C. remains constant
• D. is zero

Hint:

Capacitive reactance works against inductive reactance and reduces the net reactance.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
In an LR circuit, the impedance is \(Z = \sqrt{R^2 + X_L^2}\). The inductive reactance \(X_L\) and capacitive reactance \(X_C\) act in opposite senses in a series circuit.

Step 2: Add the capacitor:
With a capacitor in series, \(Z = \sqrt{R^2 + (X_L - X_C)^2}\).
The LR circuit is inductive, with \(X_L\) greater than \(X_C\), so \(|X_L - X_C| < X_L\).

Step 3: Effect on the current:
The impedance falls, so \(I = \dfrac{V}{Z}\) rises. The capacitor partly cancels the inductor's opposition.

Step 4: Final Answer:
The current increases, option (A).

Final Answer:
The capacitor cancels part of the inductive reactance. \[ \boxed{\text{(A) }\text{increases}} \]