energy

Question 1

what is kinetic energy?

Answer 1

anything that moves has kinetic energy e.g. a football in mid air

Question 2

what is thermal energy?

Answer 2

anything that has a temperature above absolute zero (-273°C), everything has heat energy, light and sound are also classed as thermal energy

Question 3

what is nuclear potential energy?

Answer 3

released only from nuclear stations e.g. the sun and stars

Question 4

what is chemical potential energy?

Answer 4

anything which stored energy which can be released by a chemical reaction has chemical energy e.g. food, batteries

Question 5

what is gravitational potential energy?

Answer 5

anything above the ground has gravitational potential energy e.g. aeroplanes

Question 6

what is electrostatic energy

Answer 6

whenever energy is transferred electrically in a circuit

Question 7

what is elastic potential energy?

Answer 7

anything stretched has elastic energy e.g. spring, rubber bands

Question 8

give an example of an energy transfer

Answer 8

electric energy (heat wasted) ——-> chemical potential energy ———> laptop ———> light and sound is useful but thermal energy is wasted

Question 9

what is the equation for work done?

Answer 9

work done (J) = force (N) x distance (m)

Question 10

how much work have I done if I push a table 200m with a force of 2000N?

Answer 10

200 x 2000 = 400,000 J

Question 11

what is the gravitational potential energy equation?

Answer 11

GPE = mass x gravitational field strength x height

Question 12

what is the kinetic energy equation?

Answer 12

KE = 1/2 x mass x velocity² (speed)

Question 13

what is the power equation? (PET)

Answer 13

power (W) = energy transferred (J) ÷ time taken (s)

Question 14

what is specific heat capacity?

Answer 14

the energy needed to raise the temperature of 1kg of a material by 1°C

Question 15

what is the heat transferred equation?

Answer 15

heat transferred (J) = mass (kg) x specific heat capacity (J/kg) x temperature (°C)

Question 16

what is conduction?

Answer 16

as particles heat up they become more spread out and expand, the process of heat moving through a solid, the particles are close and they pass on the energy to the next particle, occurs in metals

Question 17

what is convection?

Answer 17

when the particles vibrate, the material becomes less dense, this will cause the particles to rise, as they cool down they come back down, occurs in hot air balloons

Question 18

what is radiation?

Answer 18

heat comes out, black clothes absorb more heat than dark clothes

Question 19

what is the payback time equation?

Answer 19

payback time = cost ÷ savings per year

Question 20

what is the cost effectiveness equation?

Answer 20

cost effectiveness= savings per year ÷ cost

Question 21

what is nuclear power?

Answer 21

generates about 22% of the electricity in the UK, plans for new nuclear systems in west cumbria, they are mainly uranium and plutonium, huge amounts of it, produces pollutant gases, careful on how to store it

Question 22

what is biomass?

Answer 22

provide fuel for small electrical generators, most of the waste is wood- renewable! also used to heat up factories/homes, emit carbon dioxide when burn- but they don’s add to carbon dioxide levels- carbon neutral

Question 23

what is tidal power?

Answer 23

massive amounts of water move in and out, estimated that energy could provide 20% of Britain’s electricity, largest tide barrier generates about 250MW of electricity, barrage- dam built across river estuary, water flows out and drives turbines that are connected to generators as it does so, environmental impacts

Question 24

what is wind power?

Answer 24

blades of a wind turbine rotate with a sufficient force of wind, turns a generator which produces electricity, clean, unreliable, 11% of Britain’s electricity , turn off gas generators

Question 25

what is solar power?

Answer 25

uses energy directly from the sun to generate electricity, small scale, can be unreliable due to weather

Question 26

what is geothermal energy?

Answer 26

Iceland- 30% of their electricity, hot water used to heat homes, hot water or steam is also used to generate electricity , clean and renewable

Question 27

what is the efficiency equation?

Answer 27

efficiency = useful energy transferred by the device ÷ total energy supplied to the device x 100

Question 29

what are the UK'S electricity resources like?

Answer 29

majority natural gas, least by oil, more non renewable resources used which means that we will eventually run out

Question 30

what is non renewable energy?

Answer 30

resources that will eventually run out, most of the time they are quite bad for the environment e.g. fossil fuels