Discussion in 'Homework Help' started by bubbaUK, Dec 1, 2007.

1. ### bubbaUK Thread Starter New Member

Nov 23, 2007
6
0
Guys this is how i solved this circuit using thevenin's theorem please let me kniow if my approach was correct...

Circuit:
http://img253.imageshack.us/img253/4843/circuit1kr2.png

I was asked to find the voltage across RL using thevenin's theorem (NOT using the superposition method)

My Calculations:

I1=V1-V2/R1+R2=12V-7V/1kOhm+1.5kOhm=5/2.5=2mA
VL=V2+I1*R2= 7V-2mA*1.5kOhm=4V

2. ### hgmjr Moderator

Jan 28, 2005
9,030
214
The calculation method that you have used is not correct and so the answers you have obtained are also incorrect.

Since you have been asked to solve for the voltage and current across RL using Thevenin's Theorem then you will need to break the solution down into a couple of stages.

First take RL out of the circuit and derive the Thevenin's equivalent voltage and Thevenin's equivalent resistance of what is left.

Once you have accomplished this successfully then you can reintroduce RL back into the circuit and solve the problem as a straightforward voltage divider.

hgmjr

3. ### bubbaUK Thread Starter New Member

Nov 23, 2007
6
0
hgmjr if you were to find RL how will you do it?

Show me some working and examples..

Thanks...

4. ### hgmjr Moderator

Jan 28, 2005
9,030
214
Take a look here at the AAC ebook section on Thevenin's Theorem and see if it can help you get a clearer picture of the process involved.

hgmjr