Question

. Additional Circuit Analysis Techniques + v 10 v 10 10 1-2 1+3

I have a problem with polarities. I can find v', v'', v''' and the current also, but i dont know how to fix the right sign and i get my final answer wrong when i sum them up. Can you explain in detail how i determine the signs and polatities?
I have no problem whith the current or voltage division. Only the signs

Answer 1

The theorem used in the given example is superposition theorem In any theorem or law or analysis the below polarity marking is the same for a resistor Mark positive on the end of the resister where current enters into it (or) mark negative on the end of resistor where current comes out of it a shown above Now in (b) polarity is marked positive where the current is entering so it sis same as given polarity (reference) Here also positive is towards current entering side polarity is opposite of the given reference It is same as reward come polarity is opposite of given reference Now according to the given polarity in the question we should take into account the given reference polarity and answer accordingly since the given polarity is same a_0 in first figure (b) we take it positive and the opposite polarities as negative therefore V = + V' - V'' - V'''