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To identify the sources of energy of common items

Natural sciences

Energy transfers and forces

Educator section


3. Flashlight of camera - battery

4. Paraffin heater - paraffin

5. Gas heater - gas

6. Hair drier - electricity

7. Windmill - wind etc.

Leaner Section


Activity 3: to identify the sources of energy of common items [lo 1.2]

Think of some of the items in your homes and of any other things that are able to perform some kind of movement. Then do the following activity with a partner by trying to complete the list:

car petrol/diesel
train electricity/coal
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________

3. Fuels

The plants and animals that existed millions of years ago absorbed the sun’s energy while they were growing. They were buried under the layers of rock that eventually formed over them. Then their remains were gradually changed into oil, coal and various gases by means of chemical reactions. These fuels are known as fossil fuels . Oil, coal and gases are non-renewable , i.e. they cannot be replaced. In addition, they have to be mined from underground reserves and burning them damages our environment and our health. One non-renewable energy source that is not derived from fossils, is nuclear power. Some metals, like uranium, release enormous amounts of energy when they undergo nuclear fission. Nuclear power is utilised for manufacturing electricity, e.g. at the nuclear power station at Koeberg where electricity is generated for the use of the inhabitants of Cape Town. A small amount of nuclear power produces large amounts of nuclear fuel and causes very little environmental pollution. At present also large amounts of nuclear fuel are available. Nuclear power stations have to be built near the sea, because they need great amounts of water for cooling. This means that the energy sometimes has to be transported over long distances. Radioactive radiation can lead to health risks and it takes hundreds of years for radioactive nuclear waste to lose its radioactivity. Such waste therefore has to be buried underground in special containers for many years. Nuclear power, however, does not cause acid rain or contribute to the greenhouse effect, which is what fossil fuels do.

Because these non-renewable fuels are not expected to be available in the future, we need to conserve energy and begin to make use of alternative energy sources like the sun, water, wind, waves, tides and bio-gases for power. Great progress has already been made with the development of these forms of energy.


Learning Outcome 1: The learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts.

Assessment Standard 1.2: We know this when the learner conducts investigations and collects data: organises and uses apparatus/equipment or sources to gain and record information.

Questions & Answers

What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11077/1.1
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