Question

If I = 2.0 A in the circuit segment shown below, what is the potential difference VB - VA?

Answer 1

Answer:

10 V

Explanation:

The potential difference between two points is the amount of work required to carry a unit charge from one point to the other point. This would result in a potential difference between this two points.

The difference between the potential across two points B and A is $V_{BA}=V_B-V_A$

From the image attached:

$V_B-V_A=10-10I+20\\\\But\ I = 2A,hence:\\\\V_B-V_A=10-10(2)+20\\\\V_B-V_A=10-20+20\\\\V_B-V_A=10\ V$