Energy Transfers

Question 1

Give 5 energy stores

Answer 1

Chemical
Kinetic 
Gravitational 
Elastic
Thermal
Magnetic
Electrostatic
Nuclear

Question 2

Give 3 energy transfers

Answer 2

Mechanically
Electrically
By heating
By radiation (light and sound)

Question 3

What is the conservation of energy

Answer 3

This means there is the same amount of energy after a transfer as there was before it.

Question 4

How do you find how efficient it is

Answer 4

Useful energy output
Efficiency = ———————————- (x 100)
Total energy input

Question 5

Efficiency is always less than….% because of the unwanted energy always produced

Answer 5

100%

Question 6

Energy is often lost to heat due to…..

Answer 6

Friction

Question 7

What input of energy does a battery have

Answer 7

Chemical

Question 8

What is the output of an engine

Answer 8

Kinetic

Question 9

Give 2 objects that need light as an input

Answer 9

Solar Panels

Plants

Question 10

What state is only possible for conduction

Answer 10

Solid

Question 11

Conduction takes place by heat energy passing from….to……but the material itself does not…..

Answer 11

Particle to Particle

Move

Question 12

Which type of solid is very good at conduction

Answer 12

Metals

Question 13

What states of matter can convection only happen in

Answer 13

Liquids and gasses

Question 14

What happens when a liquid or gas is heated

Answer 14

It expands

Question 15

Give the process of convection (5 stages)

Answer 15

The liquid or pass is heated, and expands
Its volume increases
So its density decreases
So it rises
Cooler, more dense fluid sinks to take its place producing convection currents

Question 16

The…..does not rise. Instead the…….do

Answer 16

Heat

Substances

Question 17

What is different about radiation to the other heat transfers.

Answer 17

It can travel through a vacuum (needs no particles)

Question 18

What type of radiation does it use

Answer 18

Infa-red

Question 19

Give an example of radiation as a heat transfer

Answer 19

The heat from the sun to the Earth

Question 20

Can radiation happen in all states

Answer 20

Yes

Question 21

What do convection,, conduction and radiation all do the same

Answer 21

TRANSFER ENERGY!

Question 22

Which surface colour absorbs the most heat

Answer 22

Matt black

Question 23

Give 2 examples of convection in everyday life

Answer 23

Radiator

Chimney

Question 24

What does insulation do

Answer 24

Prevents energy loss (heat loss)

Question 25

What do insulating materials do

Answer 25

These are non-metals such as plastic and air to reduce the conduction of heat

Question 26

What colour is best for insulating

Answer 26

What as it is a poor absorber and emitter of heat radiation.

Question 27

By insulating, how does it help to have small pockets of air

Answer 27

This means that conduction can’t take place