forces doing work

• changes of energy in a system by

  • work done by forces
  • electrical work
  • heating
  • radiation
• work = force x distance
• Kinetic energy = 1/2 x mass x (velocity) squared
• GPE = mass x gravitational field strength x height
• law of conservation

  • energy cannot be created nor destroyed only transferred into different forms
• power = work done / time
• efficiency = useful output energy / all energy supplied
• power = rate at which energy is transferred