A small metal sphere of charge -2.0 X 10-4 C sits on the roof of a 5.0-kg cart, shown in...

A small metal sphere of charge -2.0 X 10^-4 C sits on the roof of a 5.0-kg cart, shown in Figure P14.59. The sphere moves toward another sphere of charge +1.5 * 10^-3 C, located on the wall. As it moves, the cart pulls a cable that passes over a pulley and lifts an object with mass 10 kg. The cart starts at rest 5.0 m from the wall charge. (a) What is its speed when it is 2.0 m from the wall charge? (b) What assumptions did you make?