Energy

Question 1

define energy

Answer 1

the ability to do work

Energy and work are measured in Joules (J)

Question 2

give 8 types of energy

Answer 2

kinetic, potential, chemical, nuclear, sound, light, electrical, heat

Question 3

explain kinetic energy

Answer 3

due to movement eg water flowing in a river

Question 4

explain potential energy

Answer 4

due to position (height) or tension (spring) eg water in a dam

Question 5

explain chemical energy

Answer 5

stored in chemicals, fuels or food, released during a chemical reaction eg coal, oil, batteries

Question 6

explain nuclear energy

Answer 6

stored in the nucleus of an atom eg nuclear power plant

Question 7

explain sound energy

Answer 7

due to the vibration of an object eg loudspeaker

Question 8

explain light energy

Answer 8

from the sun, heats the earth

Question 9

explain how heat energy is used

Answer 9

used to generate electricity in a power station

Question 10

The Principle of Conservation of Energy

Answer 10

Energy cannot be created or destroyed, it can only be changed from one form to another

Question 11

define non-renewable energy source

Answer 11

one that will not be regenerated in our lifetime

Question 12

give three examples of fossil fuels, an advantage and disadvantage

Answer 12

coal, oil, gas
easy to store, transport
cause global warming by co2 emissions

Question 13

give an example of nuclear fuels and an advantage and disadvantage

Answer 13

uranium
doesn’t emit co2
nuclear accidents contaminate environment

Question 14

define renewable energy source

Answer 14

never be used up

Question 15

give six examples of renewable energy sources

Answer 15

hydroelectric, biomass, wave, tidal, geothermal, wind, solar

Question 16

explain, adv, disadv of hydroelectric power

Answer 16

A dam stores water to make electricity
no co2
can flood habitats

Question 17

explain, adv, disadv of biomass power

Answer 17

Fast growing plants, rotting in a sealed tank producing methane gas
can get energy from waste (compost bin)
land used for energy crops instead of food

Question 18

explain, adv, disadv of wave energy

Answer 18

Waves can create electricity
no co2
machinery can be destroyed in storms

Question 19

explain, adv and disadv of tidal energy

Answer 19

Dam the tide and make electrify
No co2
Prevents ships and fish moving in some areas

Question 20

Explain, adv and disadv of geothermal energy

Answer 20

Hot water from deep in the earth
No co2
Expensive

Question 21

Explain, adv and disadv of wind energy

Answer 21

Wind turbines
No co2
Aesthetically bad by some ppl

Question 22

Explain, adv and disadv of solar energy

Answer 22

Solar panels
No co2
But doesn’t make energy at night

Question 23

Define sustainability

Answer 23

The conservation of balance in the worlds ecology indefinitely
Meeting the needs of the present wo affecting the ability of future generations to meet their needs

Question 24

3 ways fossil fuels are unsustainable

Answer 24

Will run out
Produce co2 global warming damage envt
Acid rain kills fish and trees

Question 25

How can we become more environmentally sustainable?

Answer 25

By choosing renewable energy sources for the future too

Question 26

How can we become more economically sustainable?

Answer 26

More govt incentives like grants to install sources of renewable energy

Question 27

How can we become more socially sustainable?

Answer 27

Educate citizens on importance of energy efficiency,

national policies that favour building renewable energy sources

Question 28

Formula for work/ energy?

Answer 28

Work (Joules) = Force(Newtons) x Distance (meters)

Question 29

Power (watts) formula

Answer 29

Power (watts) = work (joules)
——————-
Time taken (s)

Question 30

Build and test a device that transforms energy from one form to another in order to perform a function
Deceive energy changes and ways of improving efficiency

Answer 30

Solar cell connected to a fan
Light to heat and electrical
Electrical to kinetic and sound
Efficiency is the speed of the rotation of the fan
Increase efficiency by : -face the solar cell to Sun
- face the solar cell to an electrical bulb
- don’t block the light with your hand while holding the panel