The electric field at a given spot is a vector, meaning it will have magnitude and direction. It is the electrostatic force experienced by a test charge placed at that spot divided by the charge itself, = . After a rearrangement of , and q0, the equation becomes q0 =, showing that the force exerted on a charge by an electric field is proportional to the charge. In this problem, because of an electric field, a positive charge +q experiences a force of magnitude F. This force points to the left. This positive charge is then replaced with a negative charge of -q. What force, F, does the negative charge experience? a. The negative charge experiences no force because electric fields only exert forces on positive charges. b. The force has a magnitude of 2F, and points to the right. c. The force has a magnitude of F, and points to the left. d. The force has a magnitude of F, and points to the right