# Circuit question physics help?

1. Apr 13, 2013

### Questions999

We the circuit that I have attached in the post.I have to find i1 and i2. So,to find i,I have to find the equivalent resistance and then divide the voltage by the resistance and find the current.So i take the resistances 15 Ohm and 10 Ohm like they are in parallel and 8 Ohm and 24 Ohm like they are in parallel too.I add this one to the 24 Ohm on the right.Then I take this and the (10 ||15) in parallel.I add the little 3 Ohm.Then we have an equivalent 8 Ohm.SO i1=8 Ohm.Awesoome.The problem is ,how to find i2 now?
Note : If it is not clear in the figure,i1 is near 3 Ohm and i2 is near 15 Ohm.

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2. Apr 13, 2013

### Staff: Mentor

In future, please use the posting template.

If you know i1, then you know the drop across the 3Ω resistor...

3. Apr 15, 2013

### Questions999

And how would that help me?

4. Apr 15, 2013

### Staff: Mentor

It helps because you can find the potential drop across the 3Ω resistor.

5. Apr 15, 2013

### Questions999

Hehe,I get it,but how would finding that potential help me find i2? Give me a little hint :)

6. Apr 15, 2013

### Staff: Mentor

What else is connected to the other end of that resistor?

7. Apr 15, 2013

### Questions999

I don't get this.However,thank you.

8. Apr 15, 2013

### Staff: Mentor

Take a look at this diagram:

You can find the potential drop V1 across the 3Ω resistor. So what's the potential of node A with respect to the reference node?

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• ###### Fig1.gif
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9. Apr 15, 2013

### Questions999

16 Volt?

10. Apr 15, 2013

### Staff: Mentor

11. Apr 15, 2013

### Questions999

To be honest,I guessed it.I have learned the kirchoff's laws and applied them many times,but I dont know how to apply it here.

12. Apr 15, 2013

### Staff: Mentor

What potential drop did you find for V1 (across the 3Ω resistor)? Do a "KVL walk" from the reference node, up through the voltage source, through the resistor to node A, summing the potential changes.