During the time a 2.0 kg projectile moves from its initial position to a point that is displaced 20 m horizontally and 15 m above its initial position, how much work in J is done by the gravitational force on the projectile?

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples