Energy Stores And Transfers Flashcards
Closed system
System where no energy can escape to it enter from the surroundings -> total energy in a closed system never changes
Kinetic energy
Energy an object has because it is moving
Gravitational potential energy
Energy an object has because of its height above the ground
Elastic potential energy
Energy an elastic object has when it is stretched or compressed
Thermal energy
Energy an object has because of its temperature
Internal energy
The total kinetic energy and potential energy of the particles in an object
Chemical energy
Energy that can be transferred by chemical reactions
Nuclear energy
Energy stored in the nucleus of an atom
Magnetic energy
Energy a magnetic object has when it is near a magnet or in a magnetic field
Electrostatic energy
Energy a charged object has when near another charged object
Name the energy transfers
Heating
Electrical
Radiation (waves)
Mechanical (force)
3 ways of reducing waste energy
Lubrication - reduces friction so less energy is lost as heat
Streamlining - reduces air resistance or drag in water
Thermal insulation - cavity wall insulation, double glazed windows etc.
Thermal conductivity
How quickly energy is transmitted through a material by thermal conduction
Thermal insulator
Material which has a low thermal conductivity
Specific heat capacity
The amount of energy required to raise the temperature of 1kg of a substance by 1*C
Power
The rate at which work is done
Renewable energy
Can be replenished as it is used
Uses of energy resources
- transport
- electricity generation
- heat
Renewable energy resources
- solar energy
- hydroelectric energy
- tidal energy
- wave energy
- wind energy
- geothermal energy
- biofuels
Solar energy
Main uses: heating + generating electricity
Source: sunlight transfers energy to solar panels/cells
Advantages:
- cheap to run once installed
- can be used in remote places
- no greenhouse gases produced
Disadvantages:
- depends on weather
- expensive to buy + install
- cannot supply large scale demand
Hydroelectric energy
Main uses: generating electricity
Source: water flowing downhill turns generators
Advantages
- low cost to run
- no fuel costs
- reliable
- supply can meet demand
Disadvantages
- expensive to build the dams
- destroys habitats resulting in greenhouse gases produced from rotting vegetation
Tidal energy
Main uses: generating electricity
Source: turbines on tidal barrages turned by water as the tide comes in and out
Advantages
- predictable supply as there are also tides
- can produce large amounts of energy
- no fuel costs
- no greenhouse gases produced
Disadvantages
- change marine habitats and can harm animals
- restrict access for boats
- are expedience to build
- can’t control supply
Wave energy
Main uses: generating electricity
Sources: floating generators powered by waves moving up and down
Advantages
- low running cost
- no fuel costs
- no greenhouses gases produced
Disadvantages
- change marine habitats and can harm
animals
- restrict access for boats
- expensive to build
- dependent on weather
- cannot supply large scale demand
Wind energy
Main uses: generating electricity
Source: turbines turned by the wind
Advantages
- low running cost
- no fuel costs
- no greenhouses gases
Disadvantages
- supply depends on weather
- large amounts of land needed to generate enough electricity for large scale demand
- can produce noise pollution
