First of all, I assumed that this problem will involve supernode principle since there is a voltage source between V1 and V2.
Then, i came up with the following equation:
$(V1-V2)/5 + V1/5 + V2/10 - 1 = 0,$
And $V1 - V2 = 10;$
However, the answer that i have gotten was incorrect.
This problem is in my textbook under the section "Node-Voltage Analysis". However, I'm not too sure that the solution that i was provided for this question uses Node-Voltage analysis at all.
The solution was as follows:
$V1-V2 = 10$,
then they wrote down the KCL equation at a reference node: $V1/5 + V2/10 = 1$, and finally KCL at node 1 -> $(V2-V1)/5 - V1/5 = 0$
I'm confused about the provided solution mainly because:
They picked the reference node and wrote the KCL equation for that node. However, when I was learning the Node-Voltage Analysis, i thought that there is no current flowing through the ground and that I don't need to write down the equation for KCL at reference node.
They wrote down a KCL equation at reference node, how do you know that it is going to be exactly as $V1/5 + V2/10 = 1$, with V1 and V2 flowing together in one direction ? Could it be $V1/5 - V2/10 = 1$?
I'm confused about that node near V2. If I were to write a Node-Voltage equation for Node 2, for V2 would i write these: $V2/10 - 1$, or just $V2/10$ ?
- And is there a way to solve this problem using a Supernode equation?