ENERGY Above and beyond PE & KE
THE LAW: CONSERVATION OF ENERGY ∑ E1 =∑E2 Energy cannot be created or destroyed; it only changes form Energy in = energy out Heat, light and sound are common forms of energy transfer
Many types of Energy Mechanical (PE & KE) Gravitational Kinetic Chemical Nuclear Electromagnetic Thermal
Mechanical Energy A object that is able to do work has mechanical energy Examples: Cars, trains, tractors, hammers, etc
Kinetic Energy (KE) The energy of motion KE=1/2mv 2 Expressed as Joules (J) Example: Book falling from shelf
Potential Energy (PE) Stored energy “The energy of position in a force field” PE=mgh Example: Book on a shelf aka: gravitational energy
Thermal Energy When the amount of heat added to a system and something happens to the system, Thermal Energy is to blame Expressed as ΔQ Example: Heat added to water activates the water molecules, increasing the KE of the system
Chemical Energy When certain chemicals combine, energy is released Most important source of energy right now Example: Combustion of glucose (sugar) in our bodies C 6 H 12 O 6 +6O 2 6CO 2 + 6H 2 O kcal/mole
Electromagnetic Energy Waves transporting energy from one point to another Rapid variation of electric and magnetic field Examples: radio waves, microwaves, infrared radiation, visible light, ultraviolet, x-rays, gamma rays, etc
Electrical energy Energy due to the separation of charges Example: electricity!
Nuclear Energy aka mass energy E= mc 2 Einstein first observed that anything with mass has energy Unstable isotopes can be fused or split thus liberating the energy within Examples: Fission & fusion
Nuclear Energy (cont’d) An incredibly small amount of mass has an incredibly large amount of energy Energy=mass x speed of light squared Speed of light = 3 x 10 8 m/s 50 grams of mass has potential to level an entire city
Elastic/Spring PE m/physicszone/lessonch/05work/ spring/speng.htmhttp:// m/physicszone/lessonch/05work/ spring/speng.htm
PROBLEMS: _of_Physics/07_Work,%20Energy %20and%20Power/06/sp.htmlhttp:// :26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/06/sp.html
_of_Physics/07_Work,%20Energy %20and%20Power/07/sp.htmlhttp:// :26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/07/sp.html
_of_Physics/07_Work,%20Energy %20and%20Power/09/sp.htmlhttp:// :26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/09/sp.html
From Chemical to Mechanical Dry Ice Bomb
Electromagnetic to Chemical Photosynthesis
Electromagnetic to Mechanical Motor
Electromagnetic to Thermal Heater
Chemical to Electromagnetic: Battery
Mechanical to Electromagnetic Generator Windmill
Mechanical to Chemical Metabolizing food
Mechanical to Gravitational Projectile Motion
Mechanical to Thermal Friction
Gravitational to Electromagnetic Dam
Gravitational to Thermal Compression
Chemical to Thermal Combustion: refers to the rapid oxidation of fuel accompanied by the production of heat, or heat and light
Thermal to Mechanical Turbine
Thermal to Gravitational Temperature gradient: atmospheric and oceanic currents
Nuclear to Thermal Nuclear reactor