5Kinetic EnergyThe energy of motion.Is the object moving?
6Gravitational Potential Energy The energy due to the height of an object.Does the object have a height?
7Elastic Potential Energy The energy stored in a stretched or compressed spring.Is there a loaded spring?k = The spring constant (N/m)x = distance stretched or compressed (m)
8Is there a force of friction acting? Internal EnergyThe energy transferred to the molecules of the objects in the due to friction.HEATIs there a force of friction acting?f = The force of friction.∆x = The distance traveled.
9Chemical Potential Energy The energy released due to a chemical reaction.Is there a chemical reaction occurring?ASK A CHEMISTRY TEACHERFOR THE FORMULA
10Conservation of Energy For a closed system the sum of the original energy (Eo) and the work (W) done is equal to the final energy (Ef).
17Example 1:A ball is dropped from a height of 15 meters. What is its velocity just before it hits the ground?v = 0m/s15mvh = 0
18Example 2:A pendulum is released from rest at point A and has a velocity of 6 m/s at point C. Find the initial height (h) from which the pendulum was released. (Neglect air resistance)CAV=0m/sv = 6m/sh
19Example 3:A spring is compressed 20cm and launches a 400 gram block across a horizontal table. The block comes to rest after traveling 5 meters. The coefficient of friction is What is the spring constant (k)?v=0m/s5m
20Example 4:A 70kg biker has a velocity of 10m/s at the bottom of a 8 meter hill. The biker does 6000J of work in climbing the hill and 2000J is transferred to internal energy as he climbs the hill. What is the final velocity of the biker?v10m/s8m