NS LEARING

Question 1

what is energy

Answer 1

the ability to do work

Question 2

what is a source of energy

Answer 2

something that’s stores energy or provides energy that can be used

Question 3

what are fossil fuels

Answer 3

fuels that were made from living matter a long time ago

Question 4

what are the most common fossil fuels

Answer 4

oil,gas and coal

Question 5

T/F is fossil fuels running out

Answer 5

T

Question 6

what happens when you burn fossil fuels

Answer 6

it creates carbon dioxide which contributes to global warming

Question 7

what is global warming

Answer 7

gradual increase in the earth’s temperature because of gasses released such as COz when fossil fuels burn,trapping radiation within the atmosphere

Question 8

what is coal used for in SA

Answer 8

coal is used to make electricity,petrol and other synthetic fuels

Question 9

what can oil be used to make

Answer 9

petrol,diesel and paraffin

Question 10

SA doesn’t produce enough oil so what doese SA have to do

Answer 10

SA has to import oil from other countries

Question 11

where has gas reserves been found

Answer 11

under the sea near mossil bay

Question 12

what is the name of the gas reserve called near mossil bay

Answer 12

ot is called PetroSA

Question 13

what doese PetroSA do

Answer 13

thay convert the gas in to other synthetic oil for the equivalent of 45 000 barrels of importexd crude oil daily

Question 14

what doese nuclear power stations produce

Answer 14

heat energy when atoms are split in substances like urainium

Question 15

T/F are power stations expensive

Answer 15

T

Question 16

T/F in SA there are many big rivers and lakes for hydropower

Answer 16

FALSE THERE ARE NOT MANY

Question 17

what dam is the best source for hydropower in SA

Answer 17

Cahora Bassa on the zambezi river in mozambique

Question 18

how many ME or KW DOESE the dam produce

Answer 18

190 MW

Question 19

why doese SA usually not use wave and tidal power

Answer 19

SA doesn’t usually use it because SA doesn’t have suitible wave conditions and /or waves are usually too strong

Question 20

T/F in parts of he world the rise and fall of the waves are or movement of the waves is generated by electricity

Answer 20

true

Question 21

what is our most important source of energy

Answer 21

the sun

Question 22

after billions of years what will happen to the sun

Answer 22

it will burn out but for human life we consider the sun as a non renewable resource

Question 23

T/F THE SUN’S ENERGY CAN BE USED AT NIGHT TOO AND HOW

Answer 23

true,it can be. the sun’s heat heats up a type of salt to about 565 degrees the salt is used to heat water,producing steam wich creates electricity and this allows solar power stations to operate at night or during bad weather condition

Question 24

what is stored in all plant matter but mostly in wood and where can we get energy from

Answer 24

the sun is stored in all plenty matter but mostly in wood and we can get energy from animal dung

Question 25

what is heat

Answer 25

heat is what an object has because of the movement of the particles that makes up the object

Question 26

where is heat transfered from and till when doese it continue until

Answer 26

from a hotter place/object to a cooler place/object it continues until both the objects or places have the same temperature

Question 27

what is conduction

Answer 27

transfer o heat between solid objects that are in direct physical contact with each other

Question 28

what is convection

Answer 28

the way heat energy flows through liquids and gasses

Question 29

explain the convection current

Answer 29

the convection current circular movement of fluids (hot to top and cold to bottom)

Question 30

what is radiation

Answer 30

transfer of heat energy by electromagnetic waves through the air

Question 31

what is radiation

Answer 31

transfer of heat energy by electromagnetic waves through the air

Question 32

can energy be created can it be destroyed

Answer 32

no

Question 33

energy can be………from one………..to onother or……….from one to onother

Answer 33

transferred system converted