A Question about Kirchoff's Voltage Law

[bibo_dvd]

Hello Guys

My Question about Kirchoff's Law is : why in this Example
we considered that E2 is a Voltage Drop not a Voltage Rise ??

i mean why we didn't say that : +E2-V1-V2+E2=0 ?

and Thanks Guys !

 

[D H]

It's because the loop has a direction. In this case, the loop is clockwise, making E₁ positive but E₂ negative.

 

[jrive]

Pick a direction for your analysis. Assign a sign to all the voltage rises, and the opposite sign to the voltage drops. The sum of all the voltage rises =the sum of all the voltage drops around the circuit.

In your example, the current loop is clock wise, so the current flows into the negative side of E1 (voltage rise), and into the positive side of E2 (voltage drop).