What did robert millikan's oil drop experiment prove?
a. atoms are composed of positive charges.
b. it determined the actual mass of the electron.
c. matter can be conserved.
d. atoms can be neither created nor destroyed.

A2-kg bowling ball is 1 meter off the ground on a post when it falls. just before it reaches the ground,its traveling 4.4 m/s. assuming that there is no air resistant, which statement is true a. the initial potential energy is less then the final kinetic energy b. the mechanical energy is not conserved c. the mechanical energy is conserved d. the initial potential energy is greater than the final kinetic energy