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Flashcards in energy 2 Deck (49):
1

what are dull/matte surfaces good and bad for?

good at emitting and absorbing and bad at reflecting

2

what are bright/ light shiny surfaces good and bad for?

they are poor emitters and absorbers and good reflectors

3

how does heat travel?

heat travels from an area where the temperature is hot to an area where the temperature is cold until the temperatures are the same.

4

what happens when theres a larger temperature difference?

the larger temperature difference between an object and it's surroundings, the larger the rate of energy transfer

5

what can radiation do that convection and conduction can't do?

radiation can transfer energy through a vacuum (no particles needed)

6

what happens when a metal is heated?

when a metal is heated the lattice atoms vibrate more and cause the neighbouring atoms to vibrate passing these vibrations on

7

what do metals contain lots of? how do these help metals conduct?

metals contain lots of free electrons. these electrons move randomly but when a rod is heated, the free electrons gain kinetic energy and move faster

8

what happens when free electrons and lattice atoms collide?

free electrons diffuse spreading out and collide with other free electrons and lattice atoms and as a result transfer kinetic to them

9

whats a disadvantages and advantages of nuclear energy?

they release co2 and sulphur dioxide and are non-renewable but they are cheap and have a short start up time
of the fossil fuels natural gas has the shortest start up time

10

whats fossil fuels initial source of energy?

coal,oil,natural gas

11

whats fossil fuels initial energy?

chemical potential

12

whats a disadvantages and advantages of nuclear energy?

nuclear energy has the slowest start up time and creates nuclear waste but creates a lot of energy from a small amount of plutonium and it renewable

13

whats nuclears initial source of energy?

uranium or plutonium

14

whats nuclears initial energy?

nuclear

15

whats a disadvantage and advantage of hydroelectric?

it renewable source and the dams can be expensive to build

16

whats hydroelectric initial source of energy?

falling water

17

whats hydroelectric initial energy?

gravitational potentail

18

whats solar initial source of energy?

sunlight

19

whats solars initial energy?

radiation (light)

20

whats the winds initial source of energy?

the wind

21

whats winds initial energy?

kinetic or GPE

22

whats tidal initial source of energy?

the moon

23

whats tidals initial energy?

kinetic

24

whats waves initial source of energy?

the wind

25

whats waves initial energy?

kinetic or GPE

26

whats geothermal source of energy?

radioactive decay

27

whats geothermals initial energy?

thermal

28

whats biofuels source of energy?

plant matter (wood)

29

whats biofuels initial energy?

chemical potential

30

why can some renewables be unreliable ?

as they are weather dependant but do not pollute the atmosphere (except biofuels) but non-renewables can be used at anytime

31

how can pumped storage systems help?

they can meet peak demand by storing water for later

32

how can you reduce co2?

we can catch and store it (carbon capture storage) some of the best natural containers are old oil and gas fields

33

what is wind driven by?

air

34

how does fossil fuels and biofuels create energy?

the resource e.g. coal is burnt and it rises as steam into the condenser to turn the turbine which turns the generator turning coils and magnets to create electricity and after the steam has turned the turbine is condensed and falls back into water to be turned back into steam by the heat created by the resource.

35

how is nuclear energy created?

the uranium or plutonium is put into a reactor and uranium atom is spilt creating energy to heat water turning it into steam to turn the turbine and generator =electicity

36

how is geothermal energy created?

water is poured into the hot ground(as its deep down) and rises as steam to drive the turbine

37

How does solar cells create energy?

Solar cells convert suns radiation into electricity and the electric current is carried through cables throughout the house

38

How do wind turbines, wave and tidal produce energy?

Coverts kinetic energy to electrical energy. All drive a turbine directly. Water and wind can be used to drive turbines directly

39

What do pumped storage containers do?

They meet peak demand by storing water for later

40

What are hydroelectric , wave and tidal driven by?

Water

41

What fossil fuels, nuclear, geothermal and biomass driven by?

Steam

42

How can solar panels heat water?

Cold water is pumped into solar cell and radiation from sun heats water and out comes hot water

43

How can thermal energy be transferred from an object with a store of thermal energy to either the thermal energy store of the surroundings or the thermal energy store of another object.

They are called convection,conduction or radiation.

44

What do convection and conduction need energy to travel through?

Conduction and convection both use particles to transfer energy so they don’t work in vaccum

45

What is radiation also part of?

Radiation is part of the 4 types of energy transfer the other 3 are thermal, electrically and mechanically

46

How does double glazing prevent heat loss?

Reducing conduction through the glass. It does not reduce heat loss due to convection also if the gap between the panels of glass is too big convection currents form

47

What does loft insulation prevent ?

Prevents heat loss by reducing conduction through the calling into the roof this reduces convection currents that form

48

How does cavity wall insulation?

Prevents heat loss by stopping convection currents form it doesn’t allow radiation to occur through it as it is an insulator

49

How does the solar cells increase heat in water?

The sun has a large store of nuclear energy this is transferred to the earth via radiation to increase chemical potential energy store of batteries. A solar water heater uses this raidiation energy to increase the thermal energy store of water