Energy and efficiency

• Chemical


  Released during chemical reactions ( like when a fuel is burnt )
• Kinetic energy


  All moving objects have kinetic energy ( more speed more kinetic energy )
• Gravitational potential energy


  Stored energy that objects get as they are moved upwards against the force of gravity
• Elastic potential energy


  Stored energy when an elastic material is stretched or squashed ( springs back to original shape )
• Internal energy

  the total kinetic and potential energy all of the particles have in a system
• Thermal energy


  the amount of internal energy due to temperature
• Nuclear

  Energy stored in the nucleus
• What does it mean when energy is conserved?

  Energy at the start = Energy at the end
• What can't we do with energy?

  create or destroy
• How can we convert energy?

  pathways : mechanical ( moving the object ) , electricity ( using a current to transfer the energy ) , Radiation ( light , sound etc ) and heating by conduction
• How can friction be reduced?

  using a lubricant
• What is an example of an energy transfer that is a bit more complicated as it can repeat itself?

  a pendulum
• What is wasted energy?

  energy that you do not want the device to do
• What is useful energy?


  the energy you do want from the device
• What does wasted energy do?

  spreads out into the surroundings around the device
• What are the 7 types of energy store?

  — Kinetic

  - Thermal

  - Chemical

  - Gravitational potential

  - Elastic potential

  - Nuclear

  - Internal