Term 3 & 4

Question 1

energy def.

Answer 1

ability to do work

Question 2

renewable energy def.

Answer 2

energy that cannot be used up

Question 3

non-renewable energy def.

Answer 3

energy that will eventually be used up

Question 4

fossil fuels def.

Answer 4

fuels that were made from living matter a very long time ago

Question 5

non-renewable energy forms:

Answer 5

• coal
• oil
• gas
• uranium

Question 6

renewable energy forms:

Answer 6

• hydropower (energy from falling water)
• wave and tidal power
• wind energy
• solar energy
• biofuel

Question 7

potential energy def.

Answer 7

energy stored in an object or system

Question 8

types of potential energy

Answer 8

• elastic potential energy (energy stored in a stretched or compressed object)
• gravitational potential energy (energy stored in an object because of its position above the Earth)
• chemical potential energy (energy stored in the particles of substances.

Question 9

joule def.

Answer 9

unit used to measure energy

Question 10

kinetic energy def.

Answer 10

energy an object has because it is moving

Question 11

energy system def.

Answer 11

different parts that work together to store, use or give out energy, so that a specific task can be done

Question 12

Energy systems:

Answer 12

• mechanical system (uses forces and movement to do a specific task)
• thermal systems (heat energy transferred between different parts in system)
• electrical system
• biological system

Question 13

energy transfer def.

Answer 13

movement of energy from one object to another, or the change of energy from one form to another

Question 14

thermal energy def.

Answer 14

energy produced by heat

Question 15

tempurature def.

Answer 15

how hot or cold an object is

Question 16

conservation of energy def.

Answer 16

making sure that the same amount of energy is present at the end of a reaction or process as there was at the beginning

Question 17

law of conservation of energy states that…

Answer 17

energy cannot be created or destroyed

Question 18

heat def.

Answer 18

energy that an object has because of the movement in the particles that make up the object

Question 19

conduction def.

Answer 19

transfer of heat through solid objects that are in physical contact with each other

Question 20

variables def.

Answer 20

factors that can change, are observable and measurable

Question 21

fixed variable def.

Answer 21

variable that is kept constant every time the investigation is conducted

Question 22

convection def.

Answer 22

the way that heat energy flows through liquids and gases

Question 23

convection current def.

Answer 23

circular movement of fluids caused by convection

Question 24

radiation def.

Answer 24

transfer of heat energy by electromagnetic waves

Question 25

electromagnetic waves def.

Answer 25

special waves that can carry heat energy

Question 26

vacuum def.

Answer 26

a space where there is no matter

Question 27

absorbtion def.

Answer 27

process in which light strikes a surface and disappears, giving its energy to the surface in the form of heat energy.

Question 28

efficiency def.

Answer 28

being able to work well with minimum waste

Question 29

insulating materials def.

Answer 29

materials that reduce heat loss

Question 30

national electricity grid def.

Answer 30

system that generates and supplies electricity in South Africa

Question 31

solar energy def.

Answer 31

energy from the Sun

Question 32

heat and light energy uses:

Answer 32

heat - to warm up Earth | light - enables us to see and plants make photosynthesis

Question 33

Earth spinning on axis causes ...

Answer 33

night and day

Question 34

Earths tilt causes ...

Answer 34

seasons

Question 35

orbit def.

Answer 35

fixed path an object in space travels in as it revolves around another object

Question 36

revoulution def.

Answer 36

movement of an object in space around another object

Question 37

equinox and solstice dates

Answer 37

are on the 21st of June, December, March and September

Question 38

intensity of solar energy def.

Answer 38

amount of energy per unit area that reaches a place

Question 39

circle of illumination def.

Answer 39

line dividing the lit half from the dark half of the Earth

Question 40

inputs of photosynthesis

Answer 40

- carbon dioxide - light energy from the Sun - Water from the soil

Question 41

outputs of photosynthesis

Answer 41

- oxygen | - glucose (an energy rich sugar)

Question 42

Water cycle:

Answer 42

1. The Sun's energy warms water on Earth's surface and causes it to evaporate, changing into water-vapour 2. The Sun's energy heats the air, causing it to rise. The rising air then cools and water-vapour condenses into tiny droplets of water. 3. These droplets gather to form clouds 4. Rain falls from the clouds, returning back to Earth. The falling water is called precipitation

Question 43

fossils def.

Answer 43

remains of plants and animals that lived long ago

Question 44

swamps def.

Answer 44

wetlands in which tall trees and other plants grow

Question 45

Stages to make fossil fuels:

Answer 45

1. Remains of plants and animals are deposited under swamps on land or along the coast. They begin to decay 2. Soil and mud are washed into the water and form a layer on top of the plant and animal remains. These layers press down on the remains 3. More layers lead to increased pressure and over a long time. Over a long time - the lower layers of sand and mud are compacted and form sedimentary rock - the pressure changes the remains into coal, oil or gas

Question 46

phases of the moon def.

Answer 46

shapes of the lit part of the moon as seen by an observer on Earth

Question 47

phases of the moon

Answer 47

new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, waning crescent

Question 48

gravity def.

Answer 48

tendency of all objects to attract, or pull toward each other because of their mass

Question 49

mass def.

Answer 49

amount of matter in an object

Question 50

pull of gravity depends on ...

Answer 50

- how much mass they have | - how far apart their centres are

Question 51

Go to page 215

Answer 51

how did you do?

Question 52

tides def.

Answer 52

predictable, daily rise and fall of sea and ocean levels

Question 53

spring tide def.

Answer 53

tide when high tide is extra high and low tide is extra low

Question 54

tides are caused by ...

Answer 54

moon's gravitational pull

Question 55

spring tides are caused by ...

Answer 55

the combination of the Sun and moon's gravitational pull

Question 56

go to page 222

Answer 56

how did you do?

Question 57

go to page 183 and draw

Answer 57

how did you do?

Question 58

draw sun and Earth diagrams

Answer 58

how did you do?