Home
Class 12
PHYSICS
Capacitors C(1)=1 muF and C(2)=2muF are ...

Capacitors `C_(1)=1 muF` and `C_(2)=2muF` are separately charged from the same battery. They are allowed to discharge separately through equal resistors

A

The currents in the two dicharging circuits at `t=0` is zero

B

The currents in the two discharging circuits at `t=0` are equal but not zero

C

The currents in the two discharging circuits at `t=0` are unequal

D

`C_(1)` loses `50%` of its initial charge sooner than `C_(20` loses `50%` of its initial charge.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will analyze the discharging process of the capacitors \( C_1 \) and \( C_2 \) through equal resistors. ### Step 1: Write the equations for discharging current The current \( I \) during the discharging of a capacitor is given by the equation: \[ I(t) = I_0 e^{-t/(RC)} \] where \( I_0 \) is the initial current, \( R \) is the resistance, \( C \) is the capacitance, and \( t \) is time. For capacitor \( C_1 \): \[ I_1(t) = I_{10} e^{-t/(R C_1)} \] For capacitor \( C_2 \): \[ I_2(t) = I_{20} e^{-t/(R C_2)} \] ### Step 2: Determine the initial currents Since both capacitors are charged from the same battery and discharged through the same resistor, the initial currents \( I_{10} \) and \( I_{20} \) are equal: \[ I_{10} = I_{20} = \frac{V}{R} \] where \( V \) is the voltage of the battery. ### Step 3: Analyze the current at \( t = 0 \) At \( t = 0 \): \[ I_1(0) = I_{10} \quad \text{and} \quad I_2(0) = I_{20} \] Thus, both currents are equal and non-zero: \[ I_1(0) = I_2(0) = \frac{V}{R} \] ### Step 4: Determine the time for 50% discharge The charge \( Q \) on a capacitor is given by: \[ Q(t) = Q_0 e^{-t/(RC)} \] For 50% discharge, we set \( Q(t) = \frac{Q_0}{2} \): \[ \frac{Q_0}{2} = Q_0 e^{-t/(RC)} \] Dividing both sides by \( Q_0 \) and rearranging gives: \[ \frac{1}{2} = e^{-t/(RC)} \] Taking the natural logarithm: \[ \ln\left(\frac{1}{2}\right) = -\frac{t}{RC} \] Thus, \[ t = -RC \ln\left(\frac{1}{2}\right) = RC \ln(2) \] For \( C_1 \): \[ t_1 = R C_1 \ln(2) \] For \( C_2 \): \[ t_2 = R C_2 \ln(2) \] ### Step 5: Compare the discharge times Given that \( C_1 = 1 \mu F \) and \( C_2 = 2 \mu F \): \[ t_1 = R (1 \times 10^{-6}) \ln(2) \] \[ t_2 = R (2 \times 10^{-6}) \ln(2) \] Since \( C_2 > C_1 \), it follows that: \[ t_2 > t_1 \] This means \( C_1 \) discharges 50% of its charge sooner than \( C_2 \). ### Conclusion - The currents at \( t = 0 \) are equal but not zero. - Capacitor \( C_1 \) loses 50% of its initial charge sooner than capacitor \( C_2 \). ### Final Answers 1. The currents in the two discharging circuits at \( t = 0 \) are equal but not zero. 2. Capacitor \( C_1 \) loses 50% of its initial charge sooner than capacitor \( C_2 \).

To solve the problem step by step, we will analyze the discharging process of the capacitors \( C_1 \) and \( C_2 \) through equal resistors. ### Step 1: Write the equations for discharging current The current \( I \) during the discharging of a capacitor is given by the equation: \[ I(t) = I_0 e^{-t/(RC)} \] where \( I_0 \) is the initial current, \( R \) is the resistance, \( C \) is the capacitance, and \( t \) is time. ...
Promotional Banner

Similar Questions

Explore conceptually related problems

Capacitor C_(1) of the capacitance 1muF and another capacitor C_(2) of capacitance 2muF are separately charged fully by a common battery.The two capacitors are then separately allowed to discharge through equal resistors at time t=0 .

A capacitor C_1 of capacitance 1muF and a capacitor C_2 of capacitance 2muF are separately charged by a common battery for a long time. The two capacitors are then separately discharged through equal resistors. Both the discharge circuits are connected at t = 0 .

A capacitor of capacitance 500(mu)F is connected to a battery through a (10 k (Omega)) resistor.The charge stored on the capacitance 2(mu)F are separately charged by a common battery for a long time. The two capacitors are then separately discharged through equal resistors.Both the discharge circuits are connected at t=0.

Two capacitors C_1 and C_2 (C_1 gt C_2) are charged separtately to same potential. Now they are allowed to discharge through similar resistors. Initial rate of discharging will be

Two capacitors C_(1) = 4 muF and C_(2) = 2muF are charged to same potential V = 500 Volt, but with opposite polarity as shown in the figure. The switches S_(1) and S_(2) are closed.

Three capacitors C_(1)=6muF,C_(2)=12muF and C_(3)=20muF are connected to a 100 V battery, as shown in figure below: (i) Charge on each plate of capacitor C_(1) . (ii) Electrostatic potential energy stored in capacitor C_(3) .

Two capacitors of capacitances C_(1)=2muF and C_(2)=8muF are connected in series and the resulting combination is connected across a 300V battery. Calculate the charge, potential difference and energy stored in the capacitor separately.

Capacitor C_1 = 2 muF and C_2 = 3muF are connected in series to a battery of emf epsilon= 120 V whose midpoint is earthed. The wire connecting the capacitors can be earthed through a key K. Now, key K is closed. Determine the charge flowing through the sections 1, 2, and 3 in the directions indicated in figure In section 2,

Capacitor C_1 = 2 muF and C_2 = 3muF are connected in series to a battery of emf epsilon= 120 V whose midpoint is earthed. The wire connecting the capacitors can be earthed through a key K. Now, key K is closed. Determine the charge flowing through the sections 1, 2, and 3 in the directions indicated in figure In section 3,

Three capacitors C_1 = 3muF, C_2 = 6muF and C_3 = 10muF are connected to a 50 V battery as shown in the figure below: Calculate : The equivalent capacitance of the circuit between points A and B.