# Energy Transfer

• Created by: highamR15
• Created on: 26-01-19 09:56
• Energy transfer (1)
• 9 forms of Energy
• Thermal
• Chemical
• Kinnetic
• Light
• Gravitational Protential
• Elastic
• Electrical
• Nuclear
• Sound
• The law of conservation of energy
• Energy can not be created or destroyed but only transferred or transformed.
• Transformed: changes energy type
• Transferred: same energy different place
• Sankey diagram
• The width of the arrow indicates the amount if energy there is.
• Efficiency
• Efficiency is a measure of how good a machine is at its job or how wasteful the machine is.
• It is calculated by doing (useful energy out / total energy in) X 100.
• Never write fractions normal write a decimal fraction.
• Kinetic energy
• Kinetic energy= 1/2 X mass X velocity squared or Ek=1/2mv squared
• Ek=J
• m=Kg
• V squared =m/s
• Calculate the speed of a falling object
• Also called the speed it hits the group
• If we know the mass we can work out the speed (also need the height)
• Mass=balance
• Height=  meter rule
• Work
• Work is done whenever energy is converted from one form to another.
• If an object gains 100J of g.p.e. Then 100J of work has been done.
• Work done=force X distance moved in the direction of the force
• Power
• Power is the rate at which work is done.
• Power = work done /time