Energy

Question 1

Give the 8 main stores of energy

Answer 1

1) magnetic
2) internal( thermal)
3) chemical
4) kinetic
5) electrostatic
6) elastic potential
7) gravitational potential
8) nuclear

Question 2

Give the 4 main pathways for transferring energy

Answer 2

Mechanical work
Electrical work
Heating
Radiation

Question 3

Give the definition for a mechanical work pathway

Answer 3

A force moving an object through a distance

Question 4

Give the definition for an electrical work pathway

Answer 4

Charges moving due to a potential difference

Question 5

Give the definition for a heating work pathway

Answer 5

Due to temperature difference cause electrically or by chemical reaction

Question 6

Give the definition for a radiation pathway

Answer 6

Energy transferred as a wave eg. Light and infrared -the sun emits light radiation and infrared radiation

Question 7

What can energy not be?

Answer 7

Created or destroyed

Question 8

Give the formula for a change in gravitational potential energy

Answer 8

m X g X change in h
mass X gravitational field strength X change in vertical heighg

Question 9

Give the formula for amount of kinetic energy of a moving object

Answer 9

1/2 X mass X velocity^2
1/2 X mv^2

Question 10

Give an example of useful and wasted energy in an electric kettle

Answer 10

Useful- heats water
Wasted- infrared radiation transferred to the surroundings

Question 11

Give an example of useful and wasted energy in a hairdryer

Answer 11

Useful- thermal energy heating the air
Kinetic energy of the fan that blows the air
Wasted - sound radiation
Thermal energy heating the hairdryer
Infrared radiation transferred to the surroundings

Question 12

Give an example of useful and wasted energy in a lightbulb

Answer 12

Useful- light radiation given out by the hot filament
Wasted- infrared radiation transferred to the surroundings

Question 13

What does it mean if an object is very efficient?

Answer 13

It will waste very little of its input energy

Question 14

Give the formula for efficiency

Answer 14

Useful energy transferred / total energy supplied

Question 15

How do you find the percentage of efficiency

Answer 15

efficiency equation X 100

Question 16

What’s the law of conservation of energy?

Answer 16

Energy can only be transferred or dissipated( wasted) and cannot be created

Question 17

How can mechanical devises become more efficient?

Answer 17

Lubrication- reduces friction

Question 18

Why are poor conductors good at insulation?

Answer 18

Energy can’t leave the house quickly

Question 19

What are energy resources?

Answer 19

Systems that can store large amounts of energy

Question 20

Give the 9 energy stores available to produce electricity

Answer 20

Fossil fuels
Nuclear fuel
Biofuel
Wind
Hydroelectricity
Geothermal
Tidal
Water waves
Sun

Question 21

Give the global energy consumption in 2014 of oil

Answer 21

32%

Question 22

Give the global energy consumption in 2014 of coal

Answer 22

30%

Question 23

Give the global energy consumption in 2014 of gas

Answer 23

24%

Question 24

Give the global energy consumption in 2014 of hydro

Answer 24

7%

Question 25

Give the global energy consumption in 2014 of nuclear

Answer 25

4%

Question 26

Give the global energy consumption in 2014 of others

Answer 26

3%

Question 27

Give the main energy resources used today

Answer 27

Fossil fuels
Nuclear fuels
Biofuel
Water waves
Sun / solar panels
Wind/ wind turbines
Tides
Geothermal
Hydroelectricity