Question

 capacitor in series with a  resistor is connected to a 110V-60 Hz supply. What is the maximum current in the circuit? What is the time lag between current maximum and voltage maximum?   

Solution

Correct option is

3.24 A, 1.55 ms

The maximum (peak) current in a C-R circuit is given by  

            .  

,  

.  

  

                 

               .  

In C-R circuit, the voltage lags behind the current by a phase angle , where  

       .  

Putting the value of C and R, we get 

          

.  

The time lag is given by       

               

                  .

SIMILAR QUESTIONS

Q1

A 110 V-60 Hz a.c. supply is applied to a  capacitor. What is rms current in the circuit? What is the net power absorbed over a complete cycle?

Q2

An alternating voltage E = 200 sin 300t is applied across a series combination of  and L = 800 mH. Calculate the impedance of the circuit.

Q3

A coil of inductance 0.50 H and resistance  is connected to a 240 V-50 Hz a.c. supply. What are the maximum current in the coil and the time lag between voltage maximum and current maximum?

Q4

An emf E = 100 sin 314t volt is applied across a pure capacitor of 637 . Find the instantaneous current i.

Q5

An a.c. voltage V = 200 sin 314t is applied across a series C-R circuit.Where . Find the capacitive reactance.

Q6

In a series R-C circuit,  V = 100 V and . Find the current in the circuit and the voltage across the capacitor and the resistor. Is the algebraic sum of these voltages more than the source voltage? If yes, resolve the paradox. 

Q7

Calculate the rms current in an a.c. circuit containing a capacitor of  in series. The power supply in the circuit is rated 230 V, 50 Hz.

Q8

An alternating rms current of 1.5 mA and angular frequency  flows through a  capacitor in series. Calculate the rms voltage across the capacitor and the impedance of the circuit.

Q9

When an alternating voltage of 220 V is applied across a device X, a current 0.5 A flows through the circuit and is in phase with the applied voltage. When the same voltage is applied across another device Y, again the same current flows but it leads the voltage by . Compute the current in the circuit when the same voltage in applied across the series combination of X and Y.

Q10

A 20 V-5 W lamp is to run on 200 V-50 Hz a.c. mains. Find the capacitance of a capacitor required to run the lamp.