Apparatus :
Uncharged capacitor of 500µF, 5.0V power supply, rheostat, voltmeter, milliammeter, switch, connecting wires and a stop watch.
Procedure
i. Set up the apparatus as shown above.
ii. Close the switch and record the values of current, I at various time intervals. Tabulate your values in the table below:
iii. Plot a graph of current, I against time, t
iv. Plot a graph of It against time.
Observations
The charging current is initially high but gradually reduces to zero. A graph of current, I against time appears as shown below:
The charging current drops to zero when the capacitor is fully charged. As the p.d. across the capacitor increases the charge in the capacitor also increases up to a certain value. When the capacitor is fully charged, the p.d across the capacitor will be equals the p.d of the source.
A graph of p.d across the capacitor against time is exponential. A graph of It against time is also exponential.
sharon kalunda answered the question on
April 24, 2019 at 07:33