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Discharging a Capacitor

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Charging and Discharging of capacitors - definition

Charging:
When a capacitor is connected to a battery, positive charge appears on one plate and negative charge on the other. The potential difference between the plates ultimately becomes equal to the emf of the battery. The whole process takes some time and during this time there is an electric current through the connecting wires and the battery.
 where is the charge on the capacitor at time is called the time constant, is the emf of the battery.

Discharging:
If the plates of a charged capacitor are connected through a conducting wire, the capacitor gets discharged. Again there is a flow of charge through the wires and hence there is a current.

where is the charge on the capacitor at time is the charge on the capacitor at time and is called the time constant,

Current in a charging/discharging RC circuit - formula

Charging:
Discharging
where is the initial voltage.

Discharging - definition

When a charged body comes into contact with a body which is not charged, the electric charges jump from the charged body to the uncharged body till the charges on both the bodies become equal. This process is called discharging.

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