# Topic 3 Conservation of Energy Flashcards Preview

## Edexcel GCSE Combined Science Physics > Topic 3 Conservation of Energy > Flashcards

Flashcards in Topic 3 Conservation of Energy Deck (55)
1
Q

What is the unit for measuring energy?

A

joule

2
Q

What is the name for energy stored in a hot object?

A

thermal/internal

3
Q

How is energy transferred from hot objects to their surroundings?

A

4
Q

Energy stored in petrol in a car is transferred to energy stored in the moving car. What are the names for these two energy stores?

A

chemical, kinetic

5
Q

If 100J of energy is transferred into a machine, how much is transferred out?

A

100J

6
Q

In what way is most wasted energy transferred?

A

by heating

7
Q

When an object is moved to a higher position, what name is given to the energy that it then stores?

A

gravitational potential energy

8
Q

What are the energy transfers when a ball bounces?

A

kinetic, strain/elastic potential, kinetic

9
Q

What are the energy transfers when a moving car slows down?

A

kinetic ? thermal energy stored in the brakes/surroundings, energy transferred by forces

10
Q

Name three different types of object or substance that store energy in chemicals.

A

food, fuel, batteries/cells

11
Q

Name two ways in which a television transfers useful energy to its surroundings.

A

light, sound

12
Q

Name one way in which a television transfers wasted energy to its surroundings.

A

by heating

13
Q

In what way do most machines or processes transfer wasted energy to the surroundings?

A

by heating

14
Q

Name two machines in which energy transferred by heating is useful energy.

A

any two sensible answers, such as cooker or fire

15
Q

When a kettle boils water, the useful energy ends up stored as thermal energy in the hot water. Where does the wasted energy end up?

A

thermal energy in kettle/surroundings

16
Q

When a moving car brakes and comes to a stop, where does all the kinetic energy it was storing eventually end up?

A

thermal energy in the surroundings

17
Q

When a moving car hits a wall, what happens to the kinetic energy it was originally storing?

A

kinetic energy of crash fragments, transferred to surroundings by sound but all ends up as thermal energy in the surroundings

18
Q

What does dissipated mean?

A

19
Q

Which wastes more energy: a more efficient machine or a less efficient machine?

A

less efficient

20
Q

What happens to the particles in a solid when the solid gets warmer?

A

vibrate more

21
Q

One end of a metal bar is heated. What is the name for the way energy is transferred along the bar?

A

conduction

22
Q

What kind of materials are good thermal conductors?

A

metals

23
Q

Name two materials that are good thermal insulators.

A

any two from wood, plastic, wool, etc.

24
Q

What is the name for the way in which energy is transferred in a fluid

A

Convection

25
Q

What causes a convection current?

A

part of the fluid being hotter than the rest/warm fluid rises

26
Q

Materials that contain trapped air are good insulators. Why does the air need to be trapped?

A

so it cannot transfer energy by convection

27
Q

How does warmth from the Sun reach the Earth?

A

28
Q

Will a black car or a white car get hotter on a sunny day?

A

black

29
Q

Name one thing a homeowner can do to reduce the money they spend on heating.

A

any from insulate loft, fit double glazing etc.

30
Q

What is the unit for measuring energy?

A

joule

31
Q

What is the name for energy stored in an object because it is in a high position?

A

gravitational potential energy

32
Q

What is the name for energy stored in a moving object?

A

kinetic energy

33
Q

How many grams are there in a kilogram?

A

1000

34
Q

What is the law of conservation of energy?

A

total energy stays the same, or energy cannot be created or destroyed.

35
Q

A ball has 5J of gravitational potential energy before it is dropped. How much kinetic energy is it storing the moment before it hits the floor ? 0J, less than 5J, 5J, more than 5J?

A

5J

36
Q

How can you increase the gravitational potential energy stored in a box?

A

move it up, away from the Earth

37
Q

Name a store of chemical energy.

A

any from coal, oil, natural gas, food, batteries/cells

38
Q

What do we call the kind of energy stored inside atoms?

A

nuclear energy or atomic energy

39
Q

When we burn a fuel, how is the energy transferred to the surroundings?

A

by heating

40
Q

How is energy transferred to machines such as TVs and computers?

A

by electricity

41
Q

Is electricity a fuel?

A

no

42
Q

Name two fuels that are used by most vehicles on the roads.

A

petrol, diesel

43
Q

Name two fuels that we call fossil fuels.

A

any two from coal, oil, natural gas, or oil derivatives such as petrol and diesel

44
Q

What are the two products of the complete burning of fossil fuels?

A

carbon dioxide, water

45
Q

What effect does carbon dioxide in the atmosphere have on the temperature of the Earth?

A

keeps it warm

46
Q

What is the name for the idea that the Earth is getting warmer?

A

climate change/global warming

47
Q

Name four different non-renewable resources.

A

coal, oil, natural gas, nuclear fuel/uranium

48
Q

Name two different uses for natural gas.

A

power stations, heating homes, cooking

49
Q

Name the main use for coal.

A

power stations

50
Q

How is uranium used?

A

nuclear power stations

51
Q

What gas do fossil-fuel power stations emit that nuclear power stations do not?

A

carbon dioxide

52
Q

Why is adding carbon dioxide to the atmosphere a problem?

A

contributing to climate change

53
Q

Why will supplies of fossil fuels eventually run out?

A

we are using them faster than they can be replaced

54
Q

Name two forms of renewable energy.

A

two from: solar, wind, waves, tides, bio-fuel

55
Q

What is the name for a fuel made from plants or from animal wastes?

A

bio-fuel