An electric lamp connected in series with a c | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The impedance of an $A.C.$ circuit containing a resistor (lamp) and a capacitor in series is given by $Z = \sqrt{R^2 + X_C^2}$, where $X_C = \frac

Vedclass · Accepted Answer

is reduced

Vedclass · Answer

(B) The impedance of an $A.C.$ circuit containing a resistor (lamp) and a capacitor in series is given by $Z = \sqrt{R^2 + X_C^2}$, where $X_C = \frac{1}{2\pi fC}$ is the capacitive reactance.As the frequency $f$ of the source is reduced, the capacitive reactance $X_C = \frac{1}{2\pi fC}$ increases.Since $Z = \sqrt{R^2 + X_C^2}$, an increase in $X_C$ leads to an increase in the total impedance $Z$ of the circuit.The current in the circuit is given by $I = \frac{V}{Z}$. Since $V$ is constant and $Z$ increases, the current $I$ flowing through the lamp decreases.The brightness of the lamp depends on the power dissipated, $P = I^2R$. As the current $I$ decreases, the power dissipated $P$ also decreases.Therefore, the brightness of the lamp is reduced.

An electric lamp connected in series with a capacitor and an a.c. source is glowing with certain brightness. On reducing the frequency of the source, the brightness of the lamp

Similar Questions

An alternating current of frequency $f$ is flowing in a circuit containing a resistance $R$ and a choke $L$ in series. The impedance of this circuit is

In the given figure,the current amplitude is

There is a $5\,\Omega$ resistance in an $AC$ circuit. An inductance of $0.1\,H$ is connected in series with it. If the equation of the $AC$ $EMF$ is $E = 5\sin(50t)$,then the phase difference between the current and the $EMF$ is:

An $AC$ voltage source of variable angular frequency $\omega$ and fixed amplitude $V_0$ is connected in series with a capacitance $C$ and an electric bulb of resistance $R$ (inductance zero). When $\omega$ is increased,

An inductor and a resistor are connected in series to an ac supply. If the potential differences across the inductor and the resistor are $180 \ V$ and $240 \ V$ respectively,then the voltage of the ac supply is (in $V$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module