i dont get why the 6 ohm is (+) though it is written that vo=-6i
- oldschoolLv 74 weeks ago
i is defined as clockwise. That means it enters the 6Ω on the right side. The convention I was taught is that positive current enters the + side of a resistance. In this problem the equations are written using the opposite convention for KVL Thus the left side of the 6Ω is the negative side of voltage = 6i. But that is the opposite of the defined Vo. Thus Vo = -6i. They did this to trip you up obviously. They could have defined Vo as being + on the right side to match the assumed current so that Vo = 6i but they didn't to complicate the problem.
- billrussell42Lv 74 weeks ago
I would write it as
12 – 4i – 2V₀ + 4 – 6i = 0
V₀ = –6i (negative because of the signs being backwards from expected)
but it's the same, as you can multiply my equation by –1 to get his.