Energy

• What is the unit of energy?

  Joules (J)
• How many joules are in a kilojoule?

  1000 J = 1 kJ
• What is the unit of power?

  Watt (W)
• How many watts are in a kilowatt?

  1000 W = 1 kW
• Power (W) = energy transferred (J) / time taken (S)
• In science, what does work mean?

  Transfer of energy
• work done (J) = force (N) x distance (m)
• What is the equation used to work out kWh on an energy bill?

  kWh = power (kW) x time (hours)
• What happens with thermal energy?

  It always transfers heat from the hottest thing to the coldest thing until they all reach an equilibrium of heat
• Describe temperature:

  Temperature is a measure of how hot a substance is
• Describe thermal energy:

  Thermal energy is the total energy stored in all the particles in a substances
• Which type of surface is good at absorbing and emitting radiation?

  black matte
• Which type of surface is poor at absorbing and emitting radiation?

  silver shiny
• Name this image:

  A) conduction

  
• Name this image:

  A) Radiation

  
• Name this image:

  A) Convection

  
• How do you stop conduction?

  Use gases or liquids
• How do you stop convection?

  Stop gas or liquid particles moving (stop convection currents)
• How do you stop radiation?

  Use light/shiny materials