In: Physics
The potential difference across a charged capacitor is 22 V. The capacitor discharges through a fixed resistor. After a time equal to the time constant, the potential difference has reduced to V. The magnitude of V is:
Here in the question they mentioned that the capacitor is fully charged and potential difference equal to 22 volt. That means the capacitor charges to the applied voltage. Then they mentioned that the capacitor discharges through a resistor after a time equal to time constant, it's potential difference reduces to V. Then we have to find out V.For that we can take the equation for discharging of capacitor ie,
Vc is the voltage across capacitor, Vs is the applied voltage , t is the time elapsed and RC is the time constant. The solution is shown below as an image.
So the magnitude of V is 8.094 volts across the capacitor after discharge.
Hope you ok with this and thank you.