Question

potential difference is defined as

Answer 1

Potential difference is the difference in electric potential between two points A and B.



ΔV = V(B) - V(A)



Most accurately, it is the path integral of the electric field from point A to point B:



ΔV = ∫E(r)∙dl, path=A..B



This can be interpreted as the amount of work it takes to move a
positive test charge from point A to point B through the electric field.
Equivalently, this is the amount of potential energy the test charge
will gain when it moves from point A to B.