Question

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

Options

• increases.

• decreases.

• remains constant.

• falls to zero.

Answer 1

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

Explanation:

Impedance for L-R circuit,

`Z_1 = sqrt(R^2 + X_L^2)`

Impedance for L-C-R circuit,

`Z_2 = sqrt(R^2 + (X_L - X_C)^2)`

∴ Z₂ < Z₁

As impedance decreases, the current increases.