P1

• Kinetic energy (KE)


  The energy an object has because it is moving
• Gravitational potential energy (GPE)


  The energy an object has because of its position
• Elastic potential energy


  The energy stored in a springy object when you stretch or squash it
• Thermal energy


  The energy a substance has because of its temperature
• Chemical energy


  The energy stored in fuels, food, and batteries
• Conservation of energy


  Energy cannot be created or destroyed only transferred
• Work done


  The energy transferred by a force
• Dissipation


  The process of energy being transferred or lost to the surroundings
• Friction


  A force that opposes movement
• System


  An object or group of objects
• Closed system


  An isolated system where no energy transfers take place into or out of the energy stores in the system
• Useful energy


  Energy in the place it is wanted in the form that it is needed in
• Wasted energy


  Energy that is not usefully transferred, usually as thermal
• Heating


  Energy transfer method
• Waves


  Energy transfer method
• Electric current


  Energy transfer method
• Force when it moves an object

  Energy transfer method
• Falling object


  1. Decreases its GPE store

  2. Increases its KE store as it falls

  3. Waste energy transferred as thermal and sound
• Gravitational potential energy decreasing
• Kinetic energy increasing
• Heating and sound of impact
• No device can be more than 100% efficient
• Machines waste energy because of friction between their moving parts, air resistance, electrical resistance, and noise
• The more powerful an appliance, the faster the rate at which it transfers energy
• Energy is transferred by

  • Heating
  • Waves
  • Electric current
  • Force when it moves an object
• Conservation of energy in action

  • Decreases its GPE store
  • Increases its KE store as it falls
  • Waste energy transferred as thermal and sound
• Energy Resources


  • Fossil Fuels
  • Nuclear
  • Solar
  • Wave
  • Tidal
  • Wind
  • Geothermal
  • Biomass
  • Hydro-electric
• Renewable


  An energy resource that can be replenished
• Fossil Fuels


  • Low cost
  • Easily transportable
  • Reliable
  • Produces large amounts of Carbon Dioxide
  • Produces some Sulfur Dioxide
• Nuclear

  • Generates a lot of electricity
  • Reliable
  • Expensive to construct and run
  • Produces dangerous radioactive waste which will last for thousands of years
• Solar

  • No fuel costs
  • No pollution
  • Expensive to set up
  • Doesn't work at night
• Wave

  • No fuel costs
  • Reliable
  • Can damage marine ecosystems
  • Not everywhere is near water
• Tidal

  • No fuel costs
  • No pollution
  • Reliable
  • Can damage marine ecosystems
  • Not everywhere is near water
• Wind

  • No fuel costs
  • No pollution
  • Not always reliable
  • Noisy
  • Some think they are ugly (eyesore)
• Geothermal

  • No fuel costs
  • No pollution
  • Very few areas where it is accessible
• Biomass


  • Low cost
  • Readily available
  • Carbon neutral
  • Large scale land use requiring lots of water
  • Destruction of habitat to grow crops
• Hydro-electric


  • No fuel costs
  • Reliable
  • Easily controlled
  • Requires flooding land to build
• Carbon neutral: a process by which no extra carbon is released to the atmosphere