I have two question that I am having problems with. My first question is how do I find RMS voltage? In our notes in class our teacher did not go over that. MY second question is how do I find the time constant if I am given something like at t=37.5ms the resistor voltage is 1.115v. If it help I attached the assignment. I would appriciate any tips to get me started in solving these problems. Thanks

 

For your first question, you can find the approximate R.M.S. value by multiplying peak amplitude by 0.707. (or divide by 1.414).
For your second question, you need to use the capacitor charge formula;

Vc = Vs . 1- e^-t/rc

t is 37.5ms, Vs is 5V, Vc is (5 - 1.115)

Make rc the subject of the equation, and solve for your answer.

Hope this helps,

Brian

 

hint: you'll need to take natural logs of both sides in order to get rid of e.

Brian

 

hint: you'll need to take natural logs of both sides in order to get rid of e.

Brian

Alright thanks for the help!

 

Did you manage to come up with an answer?

Brian

 

Did you manage to come up with an answer?

Brian

Yeah I came up with an answer. Do you know any good websites where I can learn more about the sin waves and such? I had some trouble figuring out some of the last problems.