Energy Ability to do work or cause change

Energy Ability to do work or cause change SI Unit : Joule

Work – measure of energy that is transferred from one system to another. - occurs when a force causes an object to move

Two types of Energy: Kinetic Energy Potential Energy

Kinetic Energy (K. E. )energy of motion - depends on mass and speed

Examples of Kinetic Energy Person running Car moving Football being thrown

Kinetic Energy equation KE = ½ mass x KE = ½ 2 velocity 2 mv Units: kg(m/s)2 or Joule (J)

Potential Energy that is stored and held in readiness

Examples of Potential Energy

4 types of potential energy 1. Elastic P. E. 2. Gravitation P. E. 3. Chemical P. E. 4. Electrical P. E.

Elastic P. E Stored energy in something compressed or stretched.

Example of Elastic PE

Gravitational P. E. Energy due to height in a gravitational field GPE = 9. 8 m/s 2 x mass x height GPE = 9. 8 mh

Example of Gravitational PE

Chemical Potential Energy stored in chemical bonds Examples: food, gasoline

Electrical Potential Energy energy due to separation of charges

Calculating Potential Energy PE = (mass)(gravitational field strength)(height) or PE = m g h g = 9. 8 N/kg Units: N/m or Joule (J)

Law of Conservation of Energy • Energy cannot be created or destroyed • Energy can change from one form to another, but the total amount of energy always remains the same