4-16: Passive RC Circuit Natural Response

Passive RC Circuit Natural Response

In this lab assignment, we examine the natural response of a simple RC circuit. First, we will find the natural response by opening a switch . Second by applying a switching step voltage from an arbitrary waveform generator . Lastly, we will simply short the voltage source to observe the response. 

 Here is a table of all the formulas related to resistors, capacitors, and inductors:

Pre-Lab: Following is the schematic of our RC circuit. We did calculated time constant since we were given R and C values. We estimated intital capacitor voltage and time constant for the circuit as shown below. 

Following is an image of oscilloscope window showing the capacitor voltage response for the circuit shown in previous image where V+ is used as the voltage source. 

Theoretical value for the  time constant is much samller than the experiment value time constant. Multimeter was not functioning correct at first that cause of error was big. 

The graph for part B:

 

For part B: Theoretical value for the  time constant is much close to  the experiment value time constant, but still have big error. 

Here is the voltage graph generated by the RL circuit:

Summary: In this lab, we have successfully learned the natural response of a simple, source free RC circuit. When a constant voltage apply to the circuit, the capacitor will only charged to whatever voltage we apply, and gives a really steep exponential voltage gain when the capacitor is begging charged, and a steep exponential voltage decay when the capacitor is being discharged.