Everything

• How many energy stores are there in physics?

  Eight energy stores
• What happens to thermal energy stores as an object gets hotter?

  They increase
• What type of energy is released by a chemical reaction?

  Chemical energy
• What is kinetic energy associated with?

  Moving objects
• What increases gravitational potential energy stores?

  The height of an object
• What does elastic potential energy store relate to?

  Objects that are stretched
• What type of energy is released during nuclear reactions?

  Nuclear energy
• What do magnetic energy stores occur due to?

  Attraction and repulsion of magnets
• What do electrostatic energy stores occur due to?

  Attraction and repulsion of electrical charges
• What are the four ways energy can be transferred?

  • Mechanically (force applied)
  • By heating (hot to cold)
  • By electric work (current flow)
  • By radiation (energy via waves)
• Which three energy stores have equations you need to know?

  Kinetic, gravitational potential, elastic potential
• What is specific heat capacity?

  Energy required to raise 1 kg by 1°C
• What is the equation for energy in terms of specific heat capacity?

  Energy = mass * specific heat capacity * change in temperature
• How is power defined in physics?

  Rate at which energy is transferred
• What is the unit of power?

  Watts
• What is the equation for power in terms of energy transferred?

  Power = energy transferred / time
• What is the equation for power in terms of work done?

  Power = work done / time
• How is efficiency defined?

  Useful energy output / total energy input
• How can efficiency also be expressed in terms of power?

  Useful power output / total power input
• What are the two types of energy resources?

  • Non-renewable: will run out, cannot be reused
  • Renewable: can be reused, generally sustainable
• What are fossil fuels made from?

  Remains of living organisms
• What greenhouse gas is produced by fossil fuels?

  Carbon dioxide
• What is a disadvantage of nuclear energy?

  Produces expensive nuclear waste
• What are the advantages and disadvantages of renewable energy resources?

  Advantages:

  • Generally sustainable
  • Most don’t produce carbon dioxide

  
  

  Disadvantages:

  • Reliability issues (e.g., wind, solar)
  • Potential harm to marine life (e.g., wave, tidal)
  • Limited locations for some (e.g., hydroelectric)
• What is direct current?

  Current that flows in one direction
• What is alternating current?

  Current that changes direction
• What is the voltage of the UK mains supply?

  230 volts
• What is the frequency of the UK mains supply?

  50 Hz
• What are the three wires in a mains electricity plug?

  • Brown Live Wire: carries 230 volts
  • Blue Neutral Wire: completes the circuit
  • Green/Yellow Earth Wire: for safety
• What is the purpose of the Earth wire?

  For safety during faults
• What happens to electricity in the National Grid?

  It passes through transformers for voltage adjustment
• What is the equation for density?

  Density = mass / volume
• How can you find the volume of an object?

  Using a Eureka can to measure displaced water
• How do particles in solids differ from those in gases?

  Solids have closely packed particles
• What happens to gas pressure as temperature increases?

  Pressure increases due to faster particle movement
• What are the changes of state in terms of melting and boiling?

  • Melting: solid to liquid
  • Freezing: liquid to solid
  • Boiling: liquid to gas
  • Condensing: gas to liquid
• What is latent heat?

  Energy required to change state without temperature change
• What is specific latent heat?

  Energy required to change 1 kg of substance's state
• What is the latent heat of fusion?

  Energy for solid to liquid transition
• What is the latent heat of vaporization?

  Energy for liquid to gas transition