Calculating the Steady State Value of Vc After Opening a Switch in a RC Circuit

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
2 replies · 8K views
compEng
Messages
5
Reaction score
0
Please Help me with this problem or with understanding it. Thank you!

Homework Statement


What is the stead-state value of Vc after the switch opens? Determine how long it takes after the switch opens before Vc is within 1 percent of its stead-state value.

Homework Equations



Vc = Vie-t/RC

The Attempt at a Solution

 
Attachments
  • circ.jpg
    circ.jpg
    23.8 KB · Views: 961
Last edited:
Physics news on Phys.org
It doesn't look like you've attempted the solution. but I'll give you some tips.
when the system is in a steady state the capacitor acts as an open circuit (ie: all the current goes through the 1k resistor.)

what is the voltage across the 1k resistor at steady state: 1x10^3 x 10x10^-3
what do you know about elements connected in parallel.

I've made this part really obvious for you. finish the first part and attempt the second part and I'll give you some more help if you need it.

Good luck
 
okay i think I figured it out.

Because the capitor becomes an open circuit, and because it is in parrelel with the resistor it begins to imitate a Norton Equivilant circuit. and Vc=IR

Vc= 10 * 10-3 * 103 = 10

thank you!