Could someone help me solve this problem, or provide me with some hint on how to solve it? Two point charges, each +4.0μC, are on the x axis; one point charge is at the origin and the other is at x=8.0m. Determine the electric potential on the x axis at

(a) x=−2.0m

(b) x=10.0m

(c) At what point on the x axis is the electric potential zero?

Thanks!

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.