Two particles with charges +2e and -4e are initially very far apart (effectively an infinite distance apart). They are then fixed at positions that are 6.09 x 10-12 m apart. What is EPEfinal - EPEinitial, which is the change in the electric potential energy?

If a car is traveling on the highway at a constant velocity, the force that pushes the car forward must be a. equal to the weight of the car. b. less than the force of friction exerted upon the car. c. equal to the force of friction exerted upon the car. d. greater than the weight of the car.