Physics

• Types of energy


  • Chemical
  • Kinetic
  • Gravitational potential
  • Thermal
  • Magnetic
  • Electrical
  • Nuclear
• Thermal energy


  Energy stored as heat
• Magnetic


  Related to magnets
• Electrical


  Related to electric charges
• Nuclear


  Related to atomic nuclei
• Energy cannot be created or destroyed, only transformed
• System


  An object or group of objects
• System changes


  1. Energy is transferred

  2. Energy is changed
• Energy can only be transferred, not created or destroyed
• Power


  The rate at which energy is transferred
• Efficiency


  How good a device is at using energy, less wasted energy = more efficient
• No appliance can be 100% efficient due to the conservation of energy
• Sankey diagram


  Shows how well a machine uses energy
• Energy storage


  • Pumped storage power station
  • Gravitational potential energy in high level reservoir
  • Kinetic energy of flowing water
• Thermal conductivity


  How well a material conducts heat
• Methods of heat transfer

  • Conduction
  • Convection
  • Radiation
• Non-renewable energy resources


  • Coal
  • Oil
  • Natural gas
  • Nuclear
• Renewable energy resources


  • Biofuels
  • Wind
  • Hydroelectric
  • Geothermal
  • Tidal
  • Solar
• what is specific heat capacity

  amount of energy needed to increase temperature of 1kg of a substance by 1.C
• What is the equation for energy transfer?

  Energy transferred= power x time
• What is equation for kinetic energy?


  Ee= 0.5 x k x e(2)
• what is Hooke’s law?

  Force is proportional to distance
• Specific heat capacity


  Amount of energy needed to increase the temperature of 1kg of a substance by 1
• Material with high specific heat capacity


  Requires more energy to heat up 1kg by 1°C than a material with lower specific heat capacity
• What does renewable energy mean?

  Resources that never run out.
• What is the equation for power?

  P= w ➗t
• What is the equation for change in temperature/specific heat capacity?

  Q = mcΔT
• What is the equation for gravitational potential energy?

  mxgxh(mgh)
• what is process for conduction?

  vibrating particles pass on energy to neighbouring particle.
• why do we use water instead of oil, for radiator?

  Efficiency