energy

energy

1. ability to make changes in another system or itself

2. units:Joules

3. sources of energy

   • non-renewable: can run out, found in nature
     • fossil fuels: CO2 is spelt, remains of plants
     • nuclear energy: nuclear reaction, dangerous
       • electrical
       • thermal
   • renewable: inexhaustible
     • hydroelectric: water moving--> flood a village, build dam, expensive
     • geothermal: internal heat of the earth-->drill deep
     • solar: rays clean energy--> lot of sun hours
     • wind: clean energy-->noisy
     • tidal:seawater movement--> enviromental impact
     • biofuel

4. types of energy

   • mechanical
     • kinetic: motion, Ek=1/2mv2
       • http://www.cienciasnaturaleselena.blogspot.com.es/search/label/2%C2%BA%20E.S.O%20NATURAL%20SCIENCES
     • potencial: equilibrium & height--> Ep=mhg
   • hermal-->heat
   • nuclear-->nuclear reactiom
   • electromagnetic
   • chemical--> molecules organised
   • electrical--> neutrons protons