Energy
Energy Energy is the ability to do work Comes in many forms Measured in joules (J) Objects can gain energy when work is being done to them Kicking a football Lifting an object
Forms of Energy Mechanical – The energy associated with motion Walking or riding a bike Water in a waterfall A car or a plane
Forms of Energy Electromagnetic – moving electric charges Electricity Light
Forms of Energy Nuclear – energy from the nucleus of an atom Nucleus is split - Fission Nuclei join - Fusion
Forms of Energy Chemical – Breaking or making chemical bonds Burning rocket fuel Digesting food Playing a sport
Forms of Energy Heat – The internal motion of atoms The faster particles move, the more heat energy is produced Rubbing hands together – the friction converts mechanical energy to heat Phase changes – like melting
Energy Does a ball have energy? Does it have energy when it falls? Can energy be created in the ball? The ball had energy before it was dropped – potential energy The ball had energy as it was dropped – kinetic energy
Kinetic Energy
Potential Energy Potential Energy – the energy of position – stored energy Stretched rubber band The string on a bow before an archer shoots an arrow An object before it is dropped Undigested food
Potential Energy
Conservation of Energy The law of conservation of energy states that energy can be neither created nor destroyed Does this sound familiar? One form of energy can be converted into another - Newtons_Cradle_-_Incredible_Science.avi Why is this important?
Conservation of Energy Because we like roller coasters! In order for a roller coaster to work, energy must be conserved
Conservation of Energy
Ticket Out the Door At which point is kinetic energy the highest?
Ticket Out the Door At which point is potential energy the highest?
Conservation of Energy Design a Roller Coaster