Lesson 13i: RC Circuits
If you have a circuit with both resistors and capacitors, you call it (not surprisingly) a
RC circuit
.
•
Because of the capacitor, the circuit will behave in a particular way.
◦
At first, with the capacitor
uncharged
, DC current will flow through it without any
problem.
◦
This means that we can just do calculations based on the resistors as if the capacitor was not
even there. You can go ahead and use formulas like V = IR.
◦
Over a period of time, the voltage across the capacitor will cause it to build up charge. As
this happens the amount of current passing through the capacitor will decrease.
◦
Eventually the capacitor will be fully charged, with the same voltage as the battery. Now, no
current will flow through the circuit. You can figure out how much charge is stored
using Q = CV.
•
When we reach the point when the capacitor is fully charged (after the circuit has been turned
on for a while), we can say that the circuit is showing
steadystate behavior.
Once a circuit is steadystate, you may need to figure out a few things about the capacitors (remember,
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Fall '08
 Staff
 Capacitance, Charge, Current, RC Circuits, Energy, Electric charge, Inductor, RC circuit

Click to edit the document details