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Flashcards in P1.2 Using Energy Deck (46)
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What energy is transferred from a light bulb?

Thermal and light energy


How do you calculate energy?

Energy (kWh) = power (w) x time (h)


what are nine types of energy?

electrical, light, sound, kinetic, nuclear, thermal, gravitational potential, elastic potential, chemical energy.


what are gravitational potential energy, elastic potential and chemical energy forms of?

stored energy as they are waiting to be turned into one of the other forms.


how do you calculate the efficiency of a machine?

useful energy out divided by total energy in.


what do the arrows pointing down in a Sankey diagram represent?

The waste energy.


what are the stages of burning non-renewable sources of energy in a power station?

coal is burnt to release heat. Water is heated in the boiler and turned to steam. Steam rushes through turbine and makes it spin which turns the generator too. Electricity is produced by the spinning generator.


what are the four stages of energy transfers in a power station?

Chemical energy into heat energy into kinetic energy into electric energy.


why might people object to wind turbines being put up near where they live?

destroys the view, loud, harmful to animals.


what are three advantages of wind turbines?

renewable resource, no fossil fuels produced, running costs are low.


why are renewable sources of often used for small-scale production of electricity?

they are a good source of energy in situations where only a small amount of electricity is needed. E.g. calculators


State the types of energy.

Magnetic, Kinetic, Heat (Thermal), Light, Gravitational Potential, Chemical, Sound, Electrical, Elastic Potential, Nuclear


How do you calculate efficiency as a decimal?

Amount of useful energy/total energy


How do you calculate efficiency as a percentage?

(Amount of useful energy/total energy) x 100


what are the two advantages of hydroelectric power?

renewable, gives us free energy


what are two disadvantages of hydroelectric power?

The set up the costs are high and it destroys wildlifes habitat


hydroelectric power stations deliver energy when...?

it is needed


pumped storage power stations deliver energy that...?

they have previously stored


how does a tidal barrage work?

The tide comes in and water passes through the turbines. This builds up behind the barrage. When the tide goes out the water is allowed out through the turbine in the barrage at controlled speed. as the water passes through the turbines electricity is generated


why many people object to tidal barrage is being built?

initial costs are high, look unattractive & can prevent access for boats.


how does the wave powered generators work

wave moves water upwards forcing air out. The moving air makes the turbine spin. The spinning generator makes electricity. The spinning turbine drives a generator. The water goes down again and air is sucked downwards spinning the turbine the other way and generating more power


what are you problems with wave power?

high initial costs, spoil the view, depends on the wind so can be unreliable.


biofuels are used to generate electricity in a similar way to...?

fossil fuels


how is electricity generated using geothermal energy?

in some volcanic areas hot water and steam rise to the surface this steam can be used to drive turbines to generate electricity.


why is burning biofuels carbon neutral?

plants are used to produce biofuels therefore they are absorbing carbon dioxide from the atmosphere so no extra carbon dioxide is being burnt


what is meant by carbon capture?

collecting carbon dioxide from power stations before it's released into the atmosphere


how can captured carbon dioxide be stored?

empty gas fields, dissolved in sea water at the bottom of the ocean


what equipment do you need for high-voltage transmission?

step up transformer, pylons


why is it still cheaper to use high voltages for transmission?

less energy is wasted as heat so it saves more money


The National Grid transmit energy at.... voltage and....current?

high voltage and a low current