Unit 8: Work & Energy

Work (W), is the only change in energy (delta E). Work = Force • Distance which is also Work = Newtons • Meters. Energy / work is measured in Joules ( J). The law of conservation of energy says that energy cannot be created or destroyed, it only changes form. In other words the sum of your energy coming in is the same amount as the energy going out. There are two different kinds of energy, potential and kinetic. Potential energy is the stored energy in an object, it is based off gravity and the height you are from your equivalence point, it is based off of positioning. Kinetic energy is moving energy, it is based off of motion. For example, if plumeria flowers were falling off a plumeria tree onto the ground, the energy they would have while still connected to the branch of the tree would be all potential, because it is all stored energy and is not yet in motion. Half way to the ground the plumeria's energy would still have the same amount (because energy is never lost and is always conserved) but just be a different type, half potential and half kinetic. Right before the plumeria touches the ground, all of it's energy would be kinetic because it is at its greatest movement. As the plumeria drops from the height of the tree, it loses potential energy and gains kinetic energy.