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Natural sciences

Energy transfers and forces

Educator section

Memorandum

(a) Petrol – motor-car

Gas – stove

Coal – steam locomotive

Wood – fire to provide heat

Crude oil – aeroplane fuel is derived from it

(b) Wind-propelled devices – wind farm

Engines that move by means of used cooking-oil

Solar heating for warmth

(c) Advantages and disadvantages of nuclear fuels and fossil fuels.

(i) Fossil fuels

Advantages Disadvantages
Quite readily available. Causes air pollution – emits smoke and harmful gases.
Can easily be converted to energy. Presents a fire hazard.
Relatively inexpensive. Mining defaces the environment.

(ii) Nuclear fuels

Advantages Disadvantages
A great deal is available. Health risks caused by radioactive eradiation.
Minimal pollution of the environment. Energy must be transported over long distances, seeing that power stations have to be built near the coast because of the water cooling systems that are used.
A small amount produces a great deal of energy. Radioactive waste must be stored safely for years until the radioactivity disappears.

Leaner Section

Content

Activity 4: to list fuels and their uses [lo 1.3]

(a) Name five common fuels and one use of each:

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(b) It is very important for people to find other sources of energy. Try to suggest ways in which people can use energy differently or make use of other sources, e.g. electric cars.

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(c) Name three advantages and three disadvantages of:

(i) Fossil fuels

ADVANTAGES DISADVANTAGES
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3.___________________________________________________________ 3.___________________________________________________________

(ii) Nuclear fuels

ADVANTAGES DISADVANTAGES
1.___________________________________________________________ 1.___________________________________________________________
2.___________________________________________________________ 2.___________________________________________________________
3.___________________________________________________________ 3.___________________________________________________________

(d) Consider the sources of energy that we have been discussing and then draw up a list to show how you could conserve energy, e.g. by switching off the lights in the classroom when the sun is shining.

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4. forms of energy

The human body does not use fuel (food) in the form in which we take it. The food is broken down into simple substances that are conserved in the muscles, in the particular form that can be used by the muscles. There therefore is energy in the substances that are stored in the muscles. Energy that is stored in chemical substances like food and fuel is known as chemical energy. All fuels therefore contain chemical energy.

Chemical energy is released when some reaction occurs. If coal is burnt, for instance, it releases heat that can then be used to generate steam for a steam locomotive.

Heat energy is used every day. We need it to cook our food and to keep warm.

Heat energy boils the water in the locomotive’s kettle and this forms steam.The steam drives the locomotive.

The sun provides us with light, as do fuels and electricity. When electricity flows through the filament in a light bulb, the wire is heated and glows. It releases light energy , as well as a small amount of heat energy. Some worms, fireflies and fish also radiate light energy.

Kinetic energy results from movement. Moving water can turn a water wheel, while wind can drive a wind pump.

Energy that is stored in things and waiting to be released by some means or other is called potential energy. The spring of an air gun that is loaded has the ability to fire. We therefore say that the loaded spring has potential energy.

Assessment

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 1.3: We know this when the learner evaluates data and communicates findings: generalises in terms of relevant aspects and describes how the data support the generalisation.

Questions & Answers

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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
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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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