Topic 1 - Energy Flashcards
What are the 8 energy stores?
- kinetic
- gravitational potential
- chemical
- elastic potential
- magnetic
- electrostatic
- nuclear
- thermal
How do you remember the 8 energy stores?
8kg of cement
What are the 4 ways energy is transferred?
- mechanical work
- electrical work
- radiation (of light or sound)
- heating
Define specific heat capacity
the energy it takes to raise the temperature of 1kg of material by 1°C
Describe conduction in metals
- metals contain free electrons that move
- when the metal is heated, these electrons gain kinetic energy
- the electrons collide with other electrons and transfer some of their kinetic energy
Describe convection in fluids
- when fluids are heated, the particles gain energy
- the hot particles are less dense than the cold ones so they rise and the cooler ones take their place
- eventually the hot particles lose energy and start to fall
- this creates a current in the fluid
Define conduction
Conduction is the process where vibrating particles transfer energy to neighbouring particles
Define convection
Convection is where energetic particles move from hotter to cooler regions
What is the law of conservation of energy?
Energy can be transferred but never created or destroyed
What are some ways to insulate a house?
- double glazed windows - air gap between two sheets of glass to prevent conduction
- draught excluders
- cavity walls
Define non-renewable
They will run out someday and cause damage to the environment.
Define renewable
They will never run out and are usually kinder to the environment
Describe wind energy and some pros and cons
It uses kinetic energy from the wind to turn a generator.
Pros = no pollution, minimal running costs, land can be used for farming still
Cons = ugly, noisy, not reliable (not always windy)
Describe solar energy and some pros and cons
Generates electric currents from the sunlight.
Pros = no pollution, fairly reliable, minimal running costs
Cons = can’t increase output when there’s more demand, lots of energy used for making them, high initial costs
Describe geothermal energy and some pros and cons
The decay from radioactive elements or the heat from deep inside the earth generates energy.
Pros = reliable, no damage to environment
Cons = expensive, not many suitable places
Describe hydroelectric power and some pros and cons
Uses kinetic energy from falling water.
Pros = no pollution, minimal running costs, fairly reliable
Cons = big impact on the environment, loss of habitat, high initial costs
Describe wave power and some pros and cons
Smallwave-powered turbines are connected to a generator.
Pros = no pollution, minimal running costs
Cons = disturbing habitats, unreliable, high initial costs
Describe tidal power and some pros and cons
Using barrages to turn turbines.
Pros = no pollution, fairly reliable
Cons = altering habitat, ugly, restrict boat access
Describe bio fuels and some pros and cons
Burning plants or animal dung to produce energy.
Pros = carbon neutral??, fairly reliable
Cons = very expensive, can increase deforestation
Describe nuclear energy and some pros and cons
Fission of uranium or plutonium to produce electricity.
Pros = no greenhouse gases, reliable, small amount of waste
Cons = waste is difficult to dispose of, radioactive, accidents can be fatal
Describe fossil fuels and some pros and cons
Fossil fuels are burnt to produce energy.
Pros = pretty cheap, reliable, easy to find, large amounts of energy
Cons = pollution, non-renewable, can cause acid rain
