The discussion centers on the behavior of capacitors in RC circuits, specifically addressing the conditions under which a capacitor is replaced by a short circuit. When t>0, the capacitor is treated as an open circuit in part b, while in part c, it is replaced by a short circuit to determine the Thevenin resistance. The method involves calculating the short circuit current and open circuit voltage to find the Thevenin resistance, which is essential for determining the time constant, RC. Alternative methods such as solving differential equations or using Laplace Transforms are mentioned but deemed more complex for achieving the same result.
PREREQUISITESElectrical engineering students, circuit designers, and anyone involved in analyzing RC circuits and their transient responses.
They were looking for the resistance that the capacitor "sees" in order to determine the time constant, RC. One way to do that is to remove the capacitor and determine the Thevenin resistance as seen at those terminals. The author of the solution decided to find the Thevenin resistance by determining the short circuit current and the open circuit voltage. Divide the voltage by the current and voila, Thevenin resistance. That short circuit for the capacitor is just the application of that method.sammyqw said:
Is there any other way to find the same answer that you may know? Thanks for your help.gneill said:
I suppose one could work out and solve a differential equation for the circuit, but that would likely be a lot of work for the same result. Or one could analyze the circuit using Laplace Transforms, again arriving at the same result after more work than necessary.sammyqw said: