capacitar = Farad - F Practical to investigate the charging and discharging a capacitor 1. Set up the circuit as shown in the diagram (taking care to ensure the polarity of the capacitor is correct). A B - - - E C R 2. With the two pole switch S in position A, the capacitor will charge. 3. Move the switch to position B so that the capacitor, C, will discharge through the resistor, R. (It is well worth doing a 'trial discharge' at this point, to see how quick the discharge is so that a suitable time interval can be decided when taking voltage readings during the discharge process). 4. After the 'trial discharge' move the switch to position A to charge up the capacitor. Measure the potential difference (voltage) across the capacitor, Vo, at time 'zero' (time t = 0). 5 . To discharge the capacitor through the resistor, adjust the switch to position B and at the same time start the stopclock. Observe and record the potential difference (voltage) V readings at 10s (10 second) intervals as the capacitor discharges. (For a faster discharge, voltage readings at 5 s intervals will be sufficient). 6. Plot a graph of p.d. [potential difference/voltage] across the capacitor, V, on the y-axis against time, t. This should give an exponential decay curve. (GRAPH A) Potential Difference (V) Vale RC 2RC JAC Time (o https:/ustem.uk/activity/discharging-a-capacitor/ 7. To confirm that this is an exponential, plot a graph of In(V) on the y-axis against t. (GRAPH B) larlater HINT: In(V) means Natural Log of V [Using your calculator] 8. This will give a straight line graph with a negative gradient