Homework Help: Branch Rule problem

1. Nov 2, 2006

FocusedWolf

How do you do this problem? I've seen other branch problems where you just give + sign for current entering and - leaving and the unknown is gonna make it equal 0, but what do you do in this case?

Last edited: Nov 2, 2006
2. Nov 2, 2006

OlderDan

Are there arrows to go with all the numbers? I think you need directions on all of them.

3. Nov 2, 2006

FocusedWolf

no, infact thats a scan of a practice/old exam question...nothing like it in my physics book or homework :rofl:

4. Nov 3, 2006

OlderDan

I did not check the multiple choice answers. I suppose it is possible only one of them is a possible solution using all the different possible current directions. I think the maximum possible current would be with all inward currents (except the ammeter)

I = [10 + 4 + 4 + 5 + 8 - 3] = 28 A

and that is too much (28*60) = 1680

Any of the blue numbers could have the opposite sign. Changing the 4 to -4 gives 1200. I did not try the other possibilies.