Mechanical energy is the energy associated with the motion or position of an object.1 There are two kinds of mechanical energy: potential energy and kinetic energy. "Potential energy is a stored form of energy that can easily produce motion or kinetics energy."1 When a ball is at an elevated position, there is no potential energy being used.1,2 Also, when a ball is at the bottom of a ground there is no kinetic energy being used. However, as soon as the ball is dropped from the elevated position to the ground, it should have enough energy to bounce back up.3 The objectives of this experiment were to determine whether temperature and floor surface had an effect on potential and kinetic energy. The experiment was tested by using 18 ping pong balls from the same brand and the same materials. The balls were grouped into three different temperatures. 6 balls were kept at room temperature of 710F, another 6 balls were also kept at high temperature of 970F, and 6 other balls were kept at low temperature of 300F. The experiment was done by dropping the balls one after the other on both concreted floor and carpeted floor. The results showed that balls bounced highest at room temperature on the concreted floor. The average bounced height was 0.82 meters compared to the averaged bounced height of the carpeted floor of 0.345 meters at the same room temperature. This result supports the "law of Conservation of energy, which states that energy is neither created nor destroyed. It changes from one form of energy to another".2 Here from potential to kinetic energy and vice-versa.