Electric Circuit Analysis, Nodal Analysis and finding Voltage.

[Xiao Xiao]

Summary:: The image shows two circuits, in the first one, using Nodal Analysis we find that V1=4.8V, but in the second circuit V1=10 because using KCL - 10+V1=0. I understand what happened in the first circuit, but I don't understand what happened in the second one, they look the same to me except for the existence of a supernode in the second one, which I don't think it should affect it in that way?

Not sure if this is the right forum to post in but this is not HW help since I already know the answer.

If I apply nodal analysis on the second circuit shouldn't I get a different result for V1?

 

[Jody]

Which part is confusing you?

 

[Xiao Xiao]

Which part is confusing you?

Wait. I actually feel very stupid right now, I got the whole question wrong, I kept seeing the 10V voltage source branch as a current source branch, and got confused, but I got it now.