physics paper 1💜

• Energy stores

  • Gravitational potential
  • Elastic potential
  • Thermal
  • Chemical
  • Nuclear
  • Magnetic
  • Electrostatic
• Gravitational potential energy


  Energy an object has because of its height above the ground
• Elastic potential energy


  Energy an elastic object has when it is stretched or compressed
• Thermal energy

  Energy an object has because of its temperature (the total kinetic and potential energy of the particles in the object)
• Chemical energy


  Energy that can be transferred by chemical reactions involving foods, fuels, and the chemicals in batteries
• Nuclear energy


  Energy stored in the nucleus of an atom
• Magnetic energy


  Energy a magnetic object has when it is near a magnet or in a magnetic field
• Electrostatic energy


  Energy a charged object has when it is near another charged object
• Insulating buildings


  • Reducing the rate of heat loss from buildings
  • Thickness of walls and roof
  • Thermal conductivity of walls and roof
• Thermal insulator

  A material which has a low thermal conductivity. The rate of energy transfer through an insulator is low
• Closed system


  One where no energy can enter from the surroundings. The total energy of the system never changes
• Energy transfers

  • Heating
  • Waves
  • Electricity
  • Forces (mechanical work)
• Heating


  Energy is transferred from one object to another object with a lower temperature
• Waves


  Waves (e.g. light and sound waves) can transfer energy by radiation
• Electricity


  When an electric current flows it can transfer energy
• Forces (mechanical work)


  Energy is transferred when a force moves or changes the shape of an object
• Energy transfer rate

  Depends on the material's thermal conductivity, the temperature difference between the two sides, and the thickness of the material
• Power


  The rate of energy transfer or the amount of work done per second
• Elastic potential energy


  Depends on the spring constant and the extension of the spring (assuming the limit of proportionality has not been exceeded)
• Useful and dissipated energy

  Energy cannot be created or destroyed, it can only be transformed usefully, stored, or dissipated (wasted)
• Efficiency


  A measure of how much energy is transferred usefully, calculated as useful output energy transfer / total input energy transfer
• Key terms

  • Chemical
  • Closed system
  • Dissipated
  • Efficiency
  • Elastic potential
  • Electrostatic
  • Gravitational potential
  • Power
  • Insulator
  • Kinetic
  • Streamlining
  • System
  • Lubrication
  • Thermal
  • Magnetic
  • Nuclear
  • Work done
• Non-renewable energy resources


  • Coal
  • Oil
  • Natural gas
  • Nuclear fission
• Non-renewable energy resources


  • Not replaced as quickly as they are used
  • Examples: fossil fuels and nuclear fission
• Renewable energy resources

  • Solar
  • Hydroelectric
  • Tidal
  • Wave
  • Wind
  • Geothermal
  • Biofuel
• Renewable energy resources


  • Can be replaced at the same rate as they are used
  • Will not run out
• Renewable vs non-renewable energy resources


  Renewable resources are reliable and have low environmental impact, non-renewable resources are less reliable and have higher environmental impact
• Carbon neutral


  The amount of carbon dioxide released when the fuel is burnt is equal to the amount of carbon dioxide absorbed