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Flashcards in TOPIC 1 Deck (61):
1

What are all of the energy stores

Thermal energy stored
Kinetic energy stores
Gravitational potential
Elastic potential
Chemical energy
Magnetic energy
Electrostatic energy
Nuclear

2

How is energy transferred

Mechanically(by a force doing work) electrically (work done by moving charges), by heating or radiation (light and sound)

3

What is a system

It’s a single object or a group of objects that your interested in

4

What happens when a system changes

Energy is transferred. It can be. transferred away into or away from the system

5

What is a closed system

Systems where neither matter nor energy can enter or leave

6

What is the net change

The net change is the total energy of s closed system is always zero

7

Give different ways energy can be transferred

When a system changes
When something is heated
Or by work done

8

When can work be done

When a current flows or by a force moving an object

9

How can we tell an object has kinetic energy

When the object moves
When an object speeds and is transferred away from this store when an object slows down

10

What does the energy in the kinetic energy store depend

The objects mass and speed. The greater it’s mass and the faster it’s going, the more energy there will be in its kinetic energy store

11

What is the formula for to find out kinetic energy

E= 1/2mv2

12

What energy is transferred into the object when it is lifted

Gravitational potential. The higher the object is lifted, the more energy is transferred to this store

13

What effects the amount of energy stored in an object

Mass ,it’s height and the strength of the gravitational field the object is in

14

What is the equation to find out the change in energy in an objects g.p.e store for a change in height

E=mgh

15

Does a falling object have air resistance

No

16

What happens when an object falls give to two energy that is starts and what is transfers to

Energy form its gravitational potential energy store is transferred to oust kinetic energy store

17

What energy acts against all falling objects

Air resistance it causes some energy to be transferred to other energy stores

18

What can be done to an object that makes it turn into elastic potential energy store

Stretching or squashing

19

Energy in the elastic potential energy store of a stretched spring can be found using

E =1/2 ke2

20

What is specific heat capacity

Is the amount of energy need to raise the temperature of 1kg it a substance by 1c

21

What is the equation linked to energy transferred to specific heat capacity

Change in thermal energy (j)E =mass(kg)specific heat capacity (j/kgC)change in thermal energy temperature change (.C)

22

What is the conservation of energy principle is that energy is always conserved

Energy can be transferred usefully,stored or dissipated,but can never be create or destroyed

23

Is it true that when energy is transferred that all the energy gets transferred

No, because not all the energy is transferred usefully into the store that you want it to go. Some energy is always dissipated when an energy transfer takes place

24

What is dissipated energy called sometimes

Wasted energy
Because the energy is being stored in a way that is not useful

25

What is power

The rate of energy transferred or the rate of doing work

26

What is power measured in

Watts
One watt= 1 joule of energy transferred per second

27

What Is an advantage and a disadvantage of a powerful machine

A powerful machine if not necessarily one which can exert force. A powerful machine is one which transfers a lot of energy in a short space of time

28

Why are useful devices useful when transferring energy

They can transfer energy from one store to another

29

How can you improve the efficiency of energy transfers

By insulting objects, lubricating them or making them more streamlined

30

What is the equation of the efficiency for any energy transfer

Efficiency =useful output energy transfer \total input energy transfer

31

Give the equation for efficiency when you know the power input and output

Efficiency = useful power output/total power input

32

What generates electricity

Renewable and non-renewable

33

What are non-renewable energy

Fossil fuels and nuclear fuel

34

Where do fossil fuel form

Underground over millions of years

35

What are the three main fossil fuel

Coal
Oil
Gas

36

Give three disadvantage of fossil fuels

These will all “run out” one day
They all do damage to the environment
But they provide most of our energy

37

Why she’s renewable energy better than non-renewable energy

Because renewable energy will never run out

38

Renewable energy resources are

The sun ( solar)
Wind
Water waves
Hydro-electricity
Bio-fuel
Tides
Geothermal

39

Why are renewable energy better

These will never run out-they energy can be renewed

Most of them do damage the environment,but in less nasty ways the non-renewables

The trouble is they don’t provide much energy and some of them are unreliable because they depend on the weather

40

Where can energy resources be used

They can be used for transport
Transport is one of the most obvious places where fuel is used

41

Non-renewable energy resources are used in

Petrol and diesel powered vehicles use created from oil


Coal is used in sine old fashioned steam

Trains to boil water to produce steam

42

Renewable energy resources are used in

Vehicles that run on pure bio-fuels or a mix of a bio-fuel and petrol or diesel (only the boi fuel bit is renewable, though)

43

What else is energy resources needed for

Heating things like your home

44

How do wind turbines produce electricity

Turbines have a generator inside it- the rotating blades turn the generator and produce electricity

45

Wind turbines are not a pretty site to look at. Explain why you need 1500 wind turbines

It’s for when a coal-fired power station is removed and 1500 of them cover a lot of ground-which have a big effect on the scenery

46

How much energy do wind turbines produce

70-85%

47

Why are wind turbines not trustworthy

There’s a problem of the turbines stopping when the wind stops or if the wind is too strong

48

What are the initial costs for wind turbines

Costs are quite highly but there are no fuel costs and minimal runny costs

49

Why happens when you remove turbines

No permanent damage to the landscape
If you remove the turbines you remove the noise and the view returns to normal

50

How do solar cells generate electric current

Directly from the sun. Solar cells are often the best source of energy to charge batteries in calculators and watches which don’t use much electricity

51

Where are solar power often used

To remote places where there’s not much choice and to power electric road signs and satellites

52

Why are solar power more reliable in hotter countries

Very reliable source of energy- but only in the daytime. Solar power can still be cost/effective even in cloudy countries like Britain though

53

How are solar cells used to generate electricity

On relatively small scale

54

Where is geothermal power found

In volcanic area or where hot rocks lie quite near to the surface.

55

What damages does geothermal power do to the environment

Brilliant free energy that reliable and does very little damage to the environment

56

What is geothermal power use to generate

It generates electricity or to heat buildings directly

57

What are the main drawbacks with geothermal power

There aren’t any suitable locations for power plants, and that the cost of building a power plant Is often highly compared to the amount of energy it produces

58

What does hydro-electric power require

Usually require the flooding of valley by building a big dam

59

What is the impact of the hydro-electricity on god environment

It cause flooding of the valley and possible loss of habitat for some species

60

Why does hydro-electric effect humans

Putting hydroelectric power stations in remote valleys tends to reduce their impact on humans

61

What is a big advantage of hydro-electricity

It can provide an immediate response to an increase demand for electricity