# Physics Lab : Rc Circuit Lab

1925 Words Jan 5th, 2015 8 Pages
Physics Lab: RC Circuit Lab
Emma Chen
January 5, 2015
Team members: Alex Wang, Andy Val_
1. Objectives
The objective of this lab is to create an RC circuit that has a time constant of 10.

2. Method and Principle: The RC circuit that we created on the breadboard was a series circuit. RC circuits contain resistors and capacitors, and are connected to a voltage source. In our case, this voltage source was the battery. When we were measuring the voltage on the computer, we used a switch instead of manually connecting it, so that it would be a smoother action. When the switch is up, it is disconnected from the circuit, and when the switch is down, it is connected to the circuit. When the voltage source in a RC circuit charges a capacitor, it will produce a time- varying current, instead of a constant current. This is because when the battery charges the capacitor, the capacitor stores the electrical energy because it has an insulating gap in between the two plates. Since there is an insulating gap, the charge that comes from the battery cannot escape from the capacitor. Therefore, the positive charges will collect on one of the plates, while the negative charges will collect on the other plate. As the amount of voltage on the capacitor gets higher and higher, the more the capacitor resists adding more voltage from the battery onto itself, therefore creating the "time- varying current" mentioned previously. This will continue until the capacitor is fully charged with the…