Conservation of Energy Flashcards
What is kinetic energy?
Anything moving
What is thermal energy?
Any object with heat. The hotter the more.
What is chemical energy?
Anything that can release energy by a chemical reaction.
What is gravitational potential energy?
Anything in a gravitational field.
What is elastic potential energy?
Anything stretched.
What is electrostatic energy?
Two charges that attract or repel each other.
What is the magnetic energy?
Two magnets that attract or repel each other.
What is nuclear energy?
Atomic nuclei releases energy from this store in nuclear reactions
What is the law of conservation of energy?
Energy can be stored, transferred between stores and dissipated but it can never be created or destroyed. It is only useful when it is transferred from one store to a useful store.
What are the four ways energy can be transferred?
Mechanically - force acting on an object
Electrically - a change doing work
By heating - a hotter object to a colder object
By radiation - transferred by waves
When is energy useful?
When it is transferred from one store to another
What is the principle of conservation of energy?
Energy cannot be created or destroyed
What is non-renewable energy?
Fossil fuel and nuclear that supply most of the worlds energy but will run out someday
How are fossil fuels made?
Formed underground over a millions of year that are typically burnt to provide energy
What the 3 main fossil fuels?
- coal
- oil
- natural gas
What are the advantage of fossil fuels?
- reliable
- cheap and easy to run
What are the disadvantages of fossil fuels?
- finite
- release carbon dioxide which contributes to global warming
- releases sulfur dioxide which acidic rain
- risk of oil spillagees
What are examples of renewable energy resources?
- Bio-fuels
- wind
- sun
- hydro-electricity
- tides
What is bio-fuels?
- renewable energy resources crated from plants or animal dung
- they can solid, liquid or gas
What are the advantages of bio-fuels?
- supposedly carbon neutral but is debatable
- ## fairly reliable
What are wind-turbines?
- generate wind power
- the wind turns the blades which turn the generator and produce electricity
What are the advantages and disadvantages of wind turbines?
- Advantages = no pollution
- Disadvantages = initial costs are high, lots of them are needed to generate power, it only works when it is windy
What are solar cells?
- made from material that use energy transferred by light to create an electric current
- used in remote areas to power electric road signs and satellites
What are the advantages and disadvantages of solar cells?
- Advantages = no pollution, no running costs
- Disadvantages = only generate small scale, suitable for sunny countries, cannot produce energy when at night
What is hydro-electricity?
- involved in flooding a valley by building a big dam
- rainwater s caught and allowed out through turbines
What are the advantages and disadvantages of hydro-electricity?
- Advantages = no pollution and it can immediately respond to increased electricity so that more water can be released through the turbines to generate more electricity , reliable
- Disadvantages = cost of building is high and have a big impact on the environment
What is tidal barrages?
big dams built across river estuaries with turbines in them
What are the advantages and disadvantages of tidal barrages?
- advantages = no pollution, reliable
- disadvantages = high initial costs
