The evil scientist made a gun that shoots a negatively charged particle with the mass of a proton. When it hits an actual proton, the mass of both particles creates an explosion. The scientist uses a horizontal 2 cm diameter plate that is charged (in a vacuum) to hold the gun against gravity. a. sketch the system with the electrical field lines and the free body diagrams superimposed b. the evil scientist wants to use the ring to push the gun up from 2 cm above the ring to 15 cm above the ring to make it into a firing position. what is the linear charge density in the ring for 2 cm elevation, and t what will it change to move the gun to 15 cm