# help needed to find the output voltage

#### nepdeep

Joined Sep 14, 2011
140
I have the circuit below...they are identical ....expect from one thing...ie they have ground at different place...i tried to solve the first one...was pretty easy...simulation also gave the same result.....
but couldnot get started with second one...although i can find values by simulation...i want to know how could we possibly solve the right circuit vout..??? thanks in advance..

#### ifixit

Joined Nov 20, 2008
650

While your trying that method see if you notice a shortcut solution for this peticular circuit.

Have Fun,
Ifixit

#### chuckey

Joined Jun 4, 2007
75
step 1, combine R2 and R3 into 6K. Step 2 remove R4, now Vout = (6/11 X 30 ) -15v .= 1.636. Now short circuit voltage sources, now can be represented by a voltage of 1.636V with a resistance of 5k and 6k in parallel = 2.72 k. So Vout = 56/(2720+56) X 1.636 =.033V.
My best guess
Frank

#### nepdeep

Joined Sep 14, 2011
140
step 1, combine R2 and R3 into 6K. Step 2 remove R4, now Vout = (6/11 X 30 ) -15v .= 1.636. Now short circuit voltage sources, now can be represented by a voltage of 1.636V with a resistance of 5k and 6k in parallel = 2.72 k. So Vout = 56/(2720+56) X 1.636 =.033V.
My best guess
Frank
hey chuckey, thanks for your clever answer....i tried using the mesh analysis as follows...I still want to learn some technique from you...

How did you come up with vout= 6/11*30-15.....