# The Physics Of Mechanical And Kinetic Energies

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The mechanical, gravitational potential and kinetic energies (measured and average) showed trends with the masses of the balls. The big ball (larger mass) possessed more mechanical, gravitational potential and kinetic energy than the small ball (see summary table above) whereas the ball with the smaller mass possessed less energy correspondingly (3.9976 > 0.4588, 1.2242 > 0.0428, 6.1853 > 1.2242). This trend was consistent throughout all of the recorded results. This can be justified by the equations of mechanical, gravitational potential and kinetic energy which all include mass meaning a larger mass constitutes to more energy (see Background Information).
The calculated theoretical and measured values showed differences with the …show more content…

This is the mechanical energy. When the balls lose height, it loses potential energy but gains speed (thus gaining kinetic energy). At halfway down (0.5m), half of the potential energy has been converted to kinetic energy but the mechanical energy remains constant (see Equation 3: Mechanical Energy in Background Information and graph above). This is because of the Law of Conservation of Energy; energy cannot be created or destroyed, only converted and transferred. Eventually, there is a complete depletion of gravitational potential energy and only kinetic energy at 0m as all the gravitational potential energy has been converted during free-fall. Once in contact with the floor, the kinetic energy converted to elastic potential (deformation), sound and heat energy, then back to kinetic energy when bouncing and gaining gravitational potential energy as the height increased. The ball never goes back up to the height it was dropped; it only bounces to a new peak which is lower than the original peak height. This is because the Law of Conservation of Energy does not ‘give’ the ball more kinetic energy to bounce back up after the energy has been converted and lost to sound energy and heat energy whilst hitting the ground (hence the ‘boing’ sound it makes, which proves the Law of Conservation of Energy). This alone proves the Law of Conservation of Energy, as the ball never bounces back to the same peak. The ball should have a higher temperature than it originally