You need to SHOW your work. How else can we see what you've done right and where you've gone wrong so that we can help you get back on track towards solving it?I tried superposition method, shorted the voltage source first and then disconnect the current source but then I stuck. Secondly I tried loop equations but don't understand what the 2amps means, the resistors should determine the amps right? But then what does the 2amp current source is doing I am confused.
Huh?Makes no difference if you assume the appropriate current/electron flow direction from the voltage sources, for whichever assumption you make..
Still waiting to see your best attempt (or AN attempt). You say you tried superposition. That will work just fine. So show what you did to try to use superposition.I tried superposition method, shorted the voltage source first and then disconnect the current source but then I stuck. Secondly I tried loop equations but don't understand what the 2amps means, the resistors should determine the amps right? But then what does the 2amp current source is doing I am confused.
Apparently I wasn't clear in my short explanation.Huh?
So let's say that we have two pieces of paper, one of which says to show a current source with the arrow pointed in the direction of conventional current flow and the other says to draw it in the direction of electron flow.
Again, this leads directly to that same contradiction.Apparently I wasn't clear in my short explanation.
The drawing does not change (why would it?).
If you assume the arrow points in the direction of conventional current-flow then, to be consistent, you also must assume that current flows out of the positive terminal of the voltage source.
If you assume the arrow points in the direction of electron flow then, again to be consistent, you also must assume that the electrons flow out of the negative terminal of the voltage source.
Either way will give you the correct answer.
Of course.Again, this leads directly to that same contradiction.
Would you agree that if we build that circuit and measure the voltage across the 10 Ω resistor as indicated, that we would get a different result than if we then turn that 2 A current source around?
Because that SAME schematic can represent EITHER circuit depending on the convention used by the person DRAWING the schematic.Of course.
But why do you persist in wanting to turn the current source around, which obviously changes the circuit, and leads to the supposed contradiction?
I would agree with it IF people that used electron flow used it correctly, but they universally don't. When they say that a current is 1 A to the right, they invariably mean that the electrons are flowing to the right. Even though they acknowledge that electrons are negatively charged, the insist that there is somehow a positive amount of charge flowing to the right and then patch things up with magical mystery minus signs sprinkled through their work.The arrow can be assumed to point in the direction of either current flow, or electron flow.
It makes no difference as long as the proper direction is also assumed for the flow through the voltage sources.
It's a basic premise that all circuits can be correctly analyzed with either current flow or electron flow, as long as you are everywhere consistent in the assumption.
Do you not agree with that?
Yeah, I'm increasingly showing symptoms of that malady, myself. Glad we got it resolved.Okay, after relooking at things I realize I had my head on backwards, and the current direction of the current source arrow would have to change if you go from current flow to electron flow.
Sorry for that, I think my old timer's disease is showing.
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by Aaron Carman
by Jeff Child