A student was asked to shade in the relative amounts of the three different forms of energy at two particular stages during the flight of a model rocket. The student was asked to assume all energy before launch is in chemical potential energy and that no energy is lost. What is wrong with the way the energy levels are shaded?

A) The rocket is not high enough to achieve any amount of gravitational potential energy so this column should not be shaded. B) Chemical potential energy never decreases and the amount stays constant. C) The amount of gravitational potential energy present is zero and therefore no shading should be present in the gravitational potential energy column. D) The amount of kinetic energy present is zero and therefore no shading should be present in the kinetic energy column. E) The sum of kinetic energy and gravitational potential energy exceeds the amount of chemical potential energy lost. This means that energy has been created and this can not be true.

The Solution...

Energy can not be created or destroyed it can only change forms. The sum of kinetic and gravitational potential energies is greater than the loss of chemical potential energy. In actual fact the sum of both kinetic and gravitational potential should equal the loss in chemical potential.

(c) Dynamic Science.