A point charge with charge q1 = 3.10 μC is held stationary at the origin. A second point charge with charge q2 = -4.70 μC moves from the point ( 0.130 m , 0) to the point ( 0.290 m , 0.235 m ). How much work W is done by the electric force on the moving point charge?
- RealProLv 72 months ago
The electrostatic force between two charges q1 and q2 separated by distance r, is
k q1 q2 / r^2
As you know dW = F*dx
Integrating the expression from separation r1 to r2, regardless of the path taken, yields the work done by the electrostatic force while the two charges move from the starting to the final configuration.
W = k q1 q2 (1/r1 - 1/r2)
Which is the negative of the change in electric potential energy of the system.