ENERGY

• Energy is...


  ...the ability to do work
• unit of energy


  Joule (J) / kilojoules (kJ)
• Chemical Energy


  Energy stored in chemical bonds
• kinetic energy


  energy of motion
• gravitational energy


  energy stored in an object's height
• Vibrational energy


  A form of Kinetic Energy which causes all the molecules of an object or any kind to vibrate.
• Elastical energy


  Can be performed by stretching/squeezing or relaxing an object
• Thermal energy


  Heat energy
• Magnetic energy


  the energy of a magnetic field
• Electrostatic energy


  potential energy stored as electrical charges
• Nuclear energy


  Energy stored in the nucleus of an atom
• types of Energy pathways


  Mechanical

  Electrical

  By heat

  B radiation
• What is a system


  An object or group of objects that interact
• Principle of conservation of energy


  Energy cannot be created or destroyed but only changed from one form to another
• Where does all of our energy come from?

  sun
• In what form does all the energy from the sun come to us as

  Thermal energy in the atmosphere
• Define heat


  the amount of thermal energy something has.

  It is measured in joules (J)

  The amount of thermal energy depends on the kinetic of its particles

  The faster the particles move the more thermal energy and heat that it produces
• Define temperature


  Temperature measures how hot or cold something is.

  It is measured in degrees Celsius
• Internal energy store


  the sum of the kinetic energy and potential energy stores of all particles in the system
• What is the thermal equilibrium

  Heating always goes from a high temperature to a low temperature

  The energy flow of the hot body will decrease

  The energy flow of the clod body will increase

  Eventually they will reach the same temperature - there is no energy transfer. This is called THERMAL EQUILIBRIUM
• Conduction of heat


  The process where vibrating particles pass on their extra kinetic energy to neighbouring particles
• Convection


  The transfer of heat by the movement of a fluid
• Heat radiation/infrared


  Electromagnetic wave - travels at the speed of light.