He then takes a powerful magnet and positions it below the table and the keys. he finds that he is able to drag the keys along the table by moving the magnet. this demonstrates that a. gravitational forces are contact forces. b. gravity is proportional to mass. c. magnetic forces act at a distance. d. magnetic forces act on wooden objects. reset submit

Assume that two of the electrons at the negative terminal have attached themselves to a nearby neutral atom. there is now a negative ion with a charge -2e at this terminal. what are the electric potential and electric potential energy of the negative ion relative to the electron? the electric potential and the electric potential energy are both twice as much. the electric potential is twice as much and the electric potential energy is the same. the electric potential is the same and the electric potential energy is twice as much. the electric potential and the electric potential energy are both the same. the electric potential is the same and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron. the electric potential is twice as much and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron.