In this lab work we conducted experiment 4: Charging curve of a capacitor.
I could predict that we would charge and discharge the capacitor before observing the
experiment, and indeed we did just that, measuring the passed time.
The experiment was about how long it took for capacitors to charge and discharge. A
capacitor theoretically never reaches full charge or complete discharge, so we determine the
optimal waiting time using the 5 tau rule.
We observed two different RC circuit:
First circuit has 1M ohm resistor and 1µF capacitor. As a result of some calculations, we
determined tau is 1 second and 5 tau is 5 second. So theoretically, the capacitor should reach
optimal charge (9,57V) in 5 seconds and discharge again in another 5 seconds but we
measured charge time is 7,36 s, discharge time is 7,64 s. We have nearly %47 error.
Second circuit has 1M ohm resistor and 4,7 µF capacitor. As a result of some calculations, we
determined tau is 4,7 second and 5 tau is 23,5 second. So theoretically, the capacitor should
reach optimal charge (9,57V) in 23,5 seconds and discharge again in another 23,5 seconds but
we measured charge time is 28,16 s, discharge time is 29,57 s. We have nearly %20 error.
* Resistor error tolerances
* Capacitor error tolerance
* Contactlessly
* Capacitor ESR (Equivalent Series Resistance)