AP Physics C 2017

(^1) The actual equation sheet for the AP exam includes this equation: . To interpret this (and other point charge equations),
recognize that this equation for the force between two point charges is an amalgamation of the first two equations above: combine F = qE with
and you get .
(^2) For calculations, it might be easier to recognize that . This value, often labeled as k , shows up repeatedly in point-
charge problems.