1. Capacitors

2. Q V C = Charge is forced on to primary plate by voltage
Charge is repelled off of secondary plate creating voltage Q V
C = V

3. Charging A
p.d. across
capacitor

4. R
Discharging A
p.d. across
capacitor

5. Set up this circuit and observe the current flow. mA mA
Set up this circuit and observe the current flow.
Describe it as fully as you can.

6. What should you have observed?
Current starts high and ends low (0)
Current reduces rapidly to begin with
Current reduces more slowly as time goes on
So…
Current discharge from a capacitor is
Exponential

7. R V C mA mA
Use a voltmeter to investigate the relationship between R or C and the ‘half life’ of the voltage