I\'m confused about how to assign the voltage polarities on circuitelements. Bel

Question

I'm confused about how to assign the voltage polarities on circuitelements. Below is an example about what I'm confused about:

http://img520.imageshack.us/img520/5075/circuitly2.jpg   (sorry for the link. Can't figure out how to insertpictures...)

So applying the Kirchoff's Law to the left loop, I get:

-5 + 54000i1 - 1V + 186000i1 = 0    

So far so good. It's doing the Kirchoff's Law to the right loopthat I get confused:

If let's say we do a clockwise loop starting below the 8V, we'llget

-186000i + v + ... + 8 = 0

So in this case, how do I know where to place the positive terminalon the 1.8k resistor?

because it does make a huge difference where I place it.

Any help would be greatly appreciated, thank you.

Explanation / Answer

Applying KVL to loop1 5 - 54000 i1 + 1 - 186000 i1 = 0 240000 i1 = 6 --------------------- (1) i1 = 6 / 240000 i1 = 25A Applying KVL to loop2 8 - 18000 (30i1) + V - 186000 i1 =0 726000 ii = 8 + V V = (726000)(25) - 8 V = 18.15 - 8 V = 10.15V

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