Electricity Continued

Question 1

What are fossil fuels?

Answer 1

The remains of dead plants and animals that store energy from the sun from millions of years ago

Question 2

What are three types of fossil fuels?

Answer 2

Coal
Oil
Natural gas

Question 3

Where does the energy in fossil fuels come from?

Answer 3

The sun

Question 4

Explain how coal or fossil fuels are formed.

Answer 4

Millions of years ago, the Sun gave its energy to plants and animals. When they died, pressure from above and heat from the Earth over millions of years turned these dead plants and animals into black coal, oil or natural gas.

Question 5

What is a non-renewable resource?

Answer 5

Resources that cannot be replaced when they are used up

Question 6

Is coal a renewable or non-renewable resource? Why?

Answer 6

Non-renewable. It takes millions of years to form

Question 7

Where was coal usually formed?

Answer 7

In low-lying wetland areas

Question 8

Plans died and formed into layers of rotting material. Over time, pressure from above packed these layer together to form _______.

Answer 8

Peat

Question 9

When _______ and ________ collected on these layers they were pressed together even tighter and made a soft brown layer called ________.

Answer 9

Sand
Water
Lignite

Question 10

_________ ________ are things from our planet that will eventually run out.

Answer 10

Non-renewable resources

Question 11

Are all fossil fuels non-renewable resources?

Answer 11

Yup:)

Question 12

What is a power station?

Answer 12

A place where electricity is generated

Question 13

What is a turbine?

Answer 13

The rotating blades of a machine

Question 14

What is a generator?

Answer 14

A machine that produces electricity

Question 15

What is the step by step process from coal to kitchen light?

Answer 15

1. Coal from storage area to boiler
2. Burns, heats water in boiler
3. Hot water into steam
4. Steam turns turbine
5. The moving turbine of the generator produces electricity
6. Travels along power lines over long distances
7. Transformers at sub-stations reduce energy carried by electricity before it enters our homes
8. People use electricity

Question 16

What does Infrastructure mean?

Answer 16

The structures and other things that are needed to make sure something works properly

Question 17

Why is generating and distributing electricity costly?

Answer 17

Because of the infrastructure that is required

Question 18

What is wattage?

Answer 18

The amount of electrical power an appliance requires to work

Question 19

Why do we pay for electricity?

Answer 19

It costs hundreds of billions of rands to build coal-burning fire stations. It also costs billions to keep all the structures and equipment working properly. For these reasons, electricity is very costly. When we pay for electricity, we are paying for the amount of energy our electrical appliances use

Question 20

Why is a wattage rating helpful

Answer 20

It gives us an idea of how much electricity the appliance will use

Question 21

Power is measured in units called ______. It is shortened to __.

Answer 21

Watts
W

Question 22

Which requires more watts? Kettles or an average radio?

Answer 22

Kettles

Question 23

Why is it bad to burn coal?

Answer 23

Waste products from burning coal pollute the air. This means they make the air dangerously dirty and can cause illness such as bronchitis and asthma

Question 24

What usually uses most of a household’s electricity?

Answer 24

Hot water geysers

Question 25

What are the benefits of a solar water heater and how does it work?

Answer 25

Using solar water heaters can help us to save electricity. Solar water heaters use the energy from the sun to heat water

Question 26

What does it mean to not be energy efficient?

Answer 26

To waste a lot of energy

Question 27

What are the benefits of energy saving light bulbs?

Answer 27

They use up to 75% less power than ordinary bulbs and last up to nine times longer

Question 28

What is an illegal connection?

Answer 28

A connection of electricity wires that is not made by a qualified electrician or does not meet the standard of the electricity laws

Question 29

Name 2 types of illegal connections.

Answer 29

Sometimes people run their own cables from the homes of others, making their own connections.
People connect wires to electricity poles to steal electricity because they do not want to pay for it

Question 30

What is the main problem with illegal connections?

Answer 30

They are unsafe

Question 31

What are renewable resources?

Answer 31

Resources that will not run out

Question 32

List 3 renewable resources.

Answer 32

Energy from the Sun, wind and moving water

Question 33

Give 2 examples of using wind power.

Answer 33

Wind pumps
Wind turbines

Question 34

How does a wind pump work?

Answer 34

When the wind turns the windmill, water is pumped up from underground and stored in a dam

Question 35

How does a wind turbine work?

Answer 35

It has a wheel with blades that turn in the wind. The wheel is on a very high tower. There is a box behind the wheel with a generator inside. When the blades turn, the generator makes electricity.

Question 36

Where should you place a wind farm?

Answer 36

Where there is lots of wind

Question 37

How can you use water power?

Answer 37

Moving water has energy. Some machines use the energy in moving water to do things like grind grain

Question 38

What happens at hydro-electric power stations?

Answer 38

The energy in falling water is changed into electrical energy. The water comes from big dams across rivers and flows down large tubes to turn the turbines in the electrical generators

Question 39

Photovoltaic solar panels have photovoltaic cells. What are photovoltaic cells?

Answer 39

Devices that convert sunlight into electricity. Photovoltaic cells can also be used in small circuits to power light bulbs, small motors or other small devices