# Homework Help: Kirchoff's Law

1. Nov 10, 2012

### Cetullah

Hello dear Physics Forums community, I need your help! I m an electrical engineering student in second class, and I m stuck with a different kind of problem (probably different to me only, lawl) in the Circuit Analysis.

I believe this problem will be a stepping stone for the other problems I can't solve yet.
1. The problem statement, all variables and given/known data

In the attachment.

2. Relevant equations

Guess they are the Voltage law and Current Law.

3. The attempt at a solution

I m stuck, can't do a thing, will appreciate the attempts to guide me to solution.

Thank you!

Edit, Lol, the problem asks the voltage difference between point a,(the corner on left-top) and point b(the left-bottom corner of the loop in right)

#### Attached Files:

• ###### kirchoff.png
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2. Nov 10, 2012

### Staff: Mentor

Indicate on your diagram where currents are flowing. Then determine the potential drops across all the components. Do a "KVL walk" from point a to point b.

Hint: A continuous current requires a complete circuit.

3. Nov 10, 2012

### Cetullah

Hmm, so I guess there's no current flowing through the line in the middle?

4. Nov 10, 2012

### Staff: Mentor

That happens to be a good guess.

5. Nov 10, 2012

### Cetullah

Nice! And can I simply discard the 5v battery and the 10 ohm resistor when I m doing the KVL walk?

6. Nov 10, 2012

### Staff: Mentor

Nope. The 5V voltage remains 5V no matter what; it's an ideal supply and cannot change. What's the potential drop across the resistor if the current is zero?