28April2014

Capacitors: Discharging and Charging Properties 

The set up is used to measure the Voltage produced when the Capacitor is charged and discharged. We used LoggerPro to measure the Potential (V) verses the time to charge and discharge. This helped us fins a relation between the potential voltage and time in charging and discharging. 

Here is a diagram for the layout. To charge it we needed to set it up in series and discharge we ran the set up in parallel. We used a 3.6kOhm resistor and P=4.5V. We will used this to also determine the value of tor =Resistance *Capacitance.

This is the actual set up of the resistor in parallel with the resistor.  

While it was discharging we expected a non-linear relationship and doing come algebra we determined the unit value of tor= RC is measured in seconds.  

These graphs show the relationship of the potential verses the time and we see the discharging of the capacitor in red and charging of capacitor in blue. Here we can see the value of C for the more accurate charging fit to be 0.002276 which is a representation of C=1/tor=1/RC in the equation V=Voe^(-t/RC)

To verify the value of C we took the labeled value resistance and capacitance used in the experiment and determined the theoretical value of tor to be 0.002273. This with the experimental value in our charging circuit to be 0.13% which is a very percent error. We experienced some error when finding the value of C for the discharging unit we did it three different time and saw no change in the result. One reason that this error occurred be the result of the machine measuring the initial voltage to be 4.88V based on the value of A in the graph. But there was no visual reason for this error but if allowed more time we would of tried new instruments and compared which instrument was creating the error by process of elimination.