charging and discharging characteristics of DC
(a) Here is the information about the circuit.
Capacitor = 100 nF , Resistor = 47 kΩ ,Supply voltage = 5 V
Charging characteristic for a series capacitive circuit:
v=v(1 − e−t/RC)
Investigate what the other terms in this expression mean.
Calculate the time constant for the circuit.
Use a spreadsheet to plot the charging curve over the range 0 to
20 ms (milliseconds).
Investigate the meaning of ‘time constant’ and from your graph
estimate a value. Compare this with your calculated one.
Differentiate the charging equation and find the rate of change of
voltage at 6 ms.
From your graph measure the gradient at 6 ms and compare this with
the calculated value.
(b) Now investigate the discharging characteristic of the circuit but with a 22 kΩ resistor
Calculate and estimate the rate of change of voltage when t = T.