Energy

• Energy: the ability to do work
• Work is done when a force moves an object
• Different types of energy

  1. potential
  2. kinetic
  3. chemical
  4. light
  5. heat
  6. electrical
  7. sound
  8. nuclear
• Renewable energy

  1. hydroelectricity
  2. biomass
  3. tidal
  4. solar
  5. wind
• Non renewable energy

  1. nuclear
  2. fossil fuels
• Sun is the main source of energy
• Potential: energy that an object has due to its position or shape
• Kinetic: energy of an object in motion
• Chemical: energy stored in chemicals such as food ,batteries ,hydrocarbons(fuels)

  often released when burning
• Light: sun provides a massive amount of energy for all life on earth
• Heat: fires provide energy to heat homes
• Electrical: wire carrying electricity can be used to supply energy to machines and heaters
• Sound: form of kinetic energy created when objects vibrate

  • sounds can travel through air, metals and water
• Nuclear: when the nucleus of an atom is split it can release nuclear energy
• Hydroelectricity: rivers dammed to convert kinetic energy to electric energy
• Biomass: harvesting chemical energy from plants to fuel
• Tidal: kinetic energy from waves to produce electricity
• Wind: kinetic energy from the wind to electrical energy- wind turbines
• Fossil fuels: chemical energy from remains of plants and animals to heat, light or electrical energy
• Nuclear: energy is given off when a nucleus of radioactive elements is split (fission)
• Principle of conservation of energy

  • energy can not be created nor destroyed but can be changed from one form to another
• Ideas to make energy more sustainable

  • insulate buildings to reduce heat loss
  • recycling
  • plugging out appliances when not in use
• Calculating energy usage

  energy used to do a task= work

  work(energy) is measured in joules or J

  • work= force multiplied by distance
• power

  • rate at which work is done
  • takes work and time into consideration
  • units: joules per second or watts