energy resources

what is the magnetic energy store

the energy stored when repelling poles have been pushed closer together or when attracting poles are pulled farther apart

what is the thermal energy store

the vibrations of an object’s particles

what is the chemical energy store

the energy stored in chemical bonds, e.g food, movement (muscles), electrical cells

what is the kinetic energy store

the energy of anything moving

what is the electrostatic energy store

the energy stored when repelling charges are moved closer together or when attracting charges are pulled further apart

what is the elastic potential energy store

the energy stored when an object is stretched or squashed

what is the gravitational potential energy energy store

the energy of an object at a certain height

what is the nuclear energy store

the energy associated with nuclear interactions

what is the principle of conservation of energy

in any process energy is never created or destroyed, it is transferred from one store to another

what is the equation for efficiency

• efficiency = useful energy output/total energy output * 100%

• useful energy output = (efficiency * total energy output) / 100%

• total energy output = (useful energy output / efficiency) / 100%

how to make a sankey diagram

• the width of the arrow represents the amount of energy involved

• the arrow going straight across represents the useful energy

• the arrow going down represents the wasted energy

• the wasted + useful energy = total energy

what is the electrostatic energy store

a force moves an object through a distance

what is the elastic potential energy store

the energy stored when an object is stretched or squashed

what is the gravitational potential energy energy store

the energy of an object at a certain height

what happens in the radiation pathway

energy transferred as a wave

what is mechanical work

a force moving an object through a distance

what is electrical work

charges moving due to a potential difference

what happens in the heating pathway

temperature difference caused electrically or by chemical reaction

what is the si unit for mass

kg

what is the si unit for energy/work done

J (joules)

what is the si unit for velocity

m/s

what is the si unit for height

m

what is the si unit for acceleration

m/s²

what is the si unit for force

N (newtons)

what is the si unit for time

s

what is the si unit for power

W (watts)

advantages and disadvantages of fossil fuels

advantages

• efficient at electricity generation

• reliable (doesn’t rely on weather)

• readily available

disadvantages

• all fossil fuels release CO₂ which is a greenhouse gas

• release sulphur dioxide when combusted which produces acid rain

• increasing fuel costs

• fossil fuels are non-renewable so they will eventually run out

advantages and disadvantages of nuclear power

advantages

• reliable

• lots of uranium available

• efficient at energy generation

• no release of CO2 or sulphur dioxide: don’t produce greenhouse gases or acid rain

disadvantages

• nuclear reactors are expensive to build and maintain

• hazardous radioactive waste produced

• small risk of nuclear meltdown/accident

• non-renewable: will run out

advantages and disadvantages of wind farms

advantages

• cheap to maintain

• no pollutants produced (while operating)

• renewable

disadvantages

• expensive to build/set up

• noisy

• unreliable

• not pleasing to look at

advantages and disadvantages of geothermal energy

advantages

• renewable

• reliable

• efficient at electricity generation

• doesn’t produce pollutants

disadvantages

• can only be used in selected areas

• expensive to build

advantages and disadvantages of solar energy

advantages

• renewable

• no pollutants produced while operating

• low maintenance costs

disadvantages

• dependant on sunlight

• inefficient at electricity generation

• take up a lot of land space

advantages and disadvantages of hydroelectric power

advantages

• renewable

• low running costs

• reliable

• large amount of energy can be produced without pollution

disadvantages

• can flood land upstream

• affects local ecology

• few locations

• high upfront building costs

advantages and disadvantages of tidal power

advantages

• reliable: tides are predictable

• cheap to run

• efficient at electricity generation

• renewable

disadvantages

• expensive to set up

• hazardous to wildlife

advantages and disadvantages of biofuels

advantages

• renewable

• cheaper than fossil fuels

• burned biofuels produce a lot less CO2 (combusting plants produces as much carbon as they absorb during growth)

• reduces reliance on fossil fuels

disadvantages

• takes up lots of land

• consumes resources that are needed for food production

wind power description, energy store input, and energy pathway

• wind turns turbine directly to generate electricity

• kinetic store of wind→ kinetic store of turbine → kinetic store of generator

• mechanical

hydroelectric power description, energy store input, and energy pathway

• water is stored at a height and when it’s released, rushing water turns turbines directly to generate electricity

• gpe → kinetic via mechanical

• kinetic → electrostatic via mechanical

geothermal power description, energy store input, and energy pathway

• hot rocks underground are used to heat water to produce steam to turn turbines which produce electricity

• thermal

• heating

solar cells power description, energy store input, and energy pathway

• solar cells use light to generate electricity

• nuclear → electrosatic

• radiation

fossil fuels power description, energy store input, and energy pathway

• fossil fuels are combusted to evaporate water into steam which turns turbines, generating electricity

• chemical

• heating

nuclear power description, energy store input, and energy pathway

• nuclear fuels are reacted to boil water into steam which turns turbines to generate electricity

• Nuclear store of fuel → thermal store of water → kinetic store of turbine → kinetic store of generator

• heating

tidal power description, energy store input, and energy pathway

• the movement of water due to tides turns turbines directly to generate electricity

• kinetic energy of tides → kinetic store of turbine → kinetic store of generator

• mechanical pathway

solar panels power description, energy store input, and energy pathway

• solar panels use thermal radiation to heat water, producing warm water for household use

• nuclear → thermal

• radiation

????

biofuel description, energy store input, and energy pathway

• plant matter, ethanol or methane can be produced and used in place of fossil fuels

  • (i.e they are combusted to evaporate water into steam which turns turbines, generating electricity)

• chemical → kinetic via heating

• kinetic → electrostatic via mechanical

what is the equation for the stopping distance of a vehicle

stopping distance = thinking distance + braking distance

factors affecting vehicle thinking distance

speed

• speed of car

reaction time

• being tired

• alcohol

• drugs

• distraction

what is the thinking distance

the distance the car travels during the driver’s reaction time

what is the braking distance

the distance the car travels from the point where the brakes are applied to when the car stops

factors affecting vehicle braking distance

• speed of car

• mass of car

• condition/quality of brakes

• condition of road (i.e if it is wet or icy)

• condition of tyres (bald tyres can’t grip road properly)

what is the relationship between velocity and braking distance

braking distance is proportional to velocity²

• if velocity increases by 3, braking distance increases by 3²

how to work out the stopping distance without knowing the thinking or braking distance

• substitute stopping distance into the equation work done = force * distance moved

• to find the stopping distance, rearrange the equation to get distance moved (stopping distance) = work done / force

what is the equation for work done(/energy transferred)

• work done (J) = force (N) * distance moved (m)

• force = work done / distance moved

• distance moved = work done / force

what is the relationship between work done and energy transferred

work done is equal to energy transferred

what is the equation for gravitational potential energy

GPE = mass (kg) * gravitational field strength (N/kg) * height (m)

what is the equation for kinetic energy + how can you rearrange it

KE = ½ * mass (kg) * velocity² (m/s)

KE = ½mv²

m = 2KE/v²

v = √(2KE/m)

how does conservation of energy make a link between gravitational potential energy, kinetic energy and work

• energy transferred = work done

• energy is transferred between gpe and kinetic energy in examples such as pendulums and rollercoasters

• this makes a link between all three because work done converts gpe into kinetic energy or vice versa

how can power be defined as the rate of energy transfer

• power = work done/time

• work done = energy transferred

• if work done/time is the rate of work being done, energy transferred/time is the rate of energy being transferred

what is the equation for power

• power (W) = work done (J) / time (s)

  • p = w/t

• power can also be measured in J/s.

  • work done = energy transferred so it could also be energy transferred/time

function of the turbine

usefully converts heat energy to kinetic energy

function of the generator

usefully converts kinetic energy to electrical energy