Finding Vottage and Current Values in a Circuit

It's been a while since I last did this, but it looks like you've done it all right. I don't think you need to account for their internal resistance, because no internal resistance values are given.

 

I don't get this circuit at all. Are you saying that what appears to be a current source and a voltage source are in reality an ammeter and a voltmeter?

Whether they are or not, the circuit doesn't make sense to me. If they are sources, then how is it that you have 10amps flowing the wrong way through a voltage source and if they are meters, how is it that you have 10 amps flowing through a voltage meter (which ideally is an open circuit)

 

Well, take a look at node D. You've got 8 amps going in and 17 amps (according to you) going out. You reckon that's going to work? Do you not know how to check your work on something this simple?

EDIT: sorry ... that sounded a bit snippy. Obviously you haven't yet learned how to do/check the problems else you wouldn't be here asking.

 

Well, if you don't know the fundamental laws of circuit analysis, I don't understand why you have been given the problem.

Here's one that will get you most if not all of the way there. The sum of all the currents coming into a node has to be zero. That is, there has to be as much going out as there is coming in ("going out" is a negative "coming in").

 

you got I3 right, V1 wrong (it's -60v)

The whole circuit is nonsensical because the only way it works is if both R1 and R2 have NEGATIVE resistance values.

I think you must have copied something wrong in stating the problem.

 

Guy, you don't even seem to be able to do simple arithmetic. I'm not trying to be harsh with you here, but this is getting ridiculous.

I2 = 5 - 8 = -3

HOW can you not get that? What did I tell you about the sum of the currents into a node?

 

http://en.wikipedia.org/wiki/Current_source This webpage suggests that the symbols are a current source and a voltage source.

Assuming this is true, we can calculate all the currents. And then we can calculate the sum of voltages around a loop, but then it doesn't come out right. The voltage source in the middle would have to be something different to agree with the rest of the circuit diagram.

So I think something with the diagram is wrong...

 

No, that's not true. I got perfectly good solution for all nodes and loops ASSUMING that the two resistors are, as I said, both NEGATIVE in resistance value. Read my post #9

 

Even if we did allow negative resistance, it still cannot be made to be consistent. Remember that there are 4 different closed loops, and the directed sum of the potential differences around any closed loop must equal zero. In this circuit, we cannot make this true. So for the circuit to be correct, it must disobey Kirchhoff's second law.

 

OOPS ... you're right. In concentrating on making the currents come out right, I negleced to check the loop voltages.

Besides, haveing a 10am reverse current going through a REAL 50v power supply would result in sparks, heat, melted wired, and general chaos.