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Natural sciences

Grade 8

Energy: electricity, heat and light

Module 10

Heat and temperature

Heat is a type of energy – the energy of the movement of particles. Temperature is the measure of how fast the molecules are moving

How do we measure temperature?

We use a thermometer that consists of a glass tube filled with a liquid such as mercury, which expands when it is warmed.

What is absolute zero ?

The lowest temperature possible, at which it becomes impossible for molecules or atoms to move. This occurs at –273,15 ºC or at 0 on the Kelvin scale. This low temperature was measured in a Finnish laboratory.

Find out what the Kelvin scale is.

You probably know that temperature can be measured on a Celsius scale or on a Fahrenheit scale. Temperatures used to be measured in Fahrenheit, so you may still find appliances that are marked in Fahrenheit, but most appliances nowadays use the Celsius scale.

How do you convert Fahrenheit to Celsius?

Subtract 32 and then divide by 9 and multiply by 5

F to C therefore is (-32 ÷ 9 x 5)

For Celsius to Fahrenheit it is:

÷ 5 x 9 + 32


To understand temperature conversions [lo 2.4]

Assignment 1:

Do you know the following?

1. The highest temperature ever recorded on earth is 720 million ºF. It was recorded during nuclear fusion, in the USA.

What would this be in ºC?

2. The highest air temperature has been measured in Libya, at 58 ºC.

What is this in ºF?

3. The lowest air temperature was recorded in Antarctica when the thernometer registered –190 ºF.

What is this in ºC?

Try: www.convert-me.com

Assessment of Temperature Conversions

Were you able to do the conversions?

[LO 2.4]

Heat Transfer


To determine terms and concepts involved with the transfer of heat [lo 2.1, lo 2.3, lo 2.4]

Assignment 1:


There are different terms for describing the transfer of heat:


Assessment of Terms

Were you able to identify the terms?

[LO 2.4]

Heat and Water

Water has a remarkable capacity for retaining heat.

Much energy is needed for the temperature of water to increase or decrease by 1 ºC.

Various factors influence heat retention by water:

  • Water is a liquid.
  • Water is transparent and light beams can penetrate to a depth of 20 m.
  • A mass of water has waves and currents and vertical movement that can distribute heat.

If you compare the heat retention capacity of the land and the oceans, you will realise that there is a considerable difference.

Capacity for heat

We know that heat causes changes in temperature and that a unit of heat is measured in Joule as it is a type of energy.

Specific heat capacity is the amount of heat that is transferred (required or released) when the temperature of a substance changes by 1 ºC or 1 K.

Water is the most expensive substance to heat because great amounts of heat are required to raise the temperature of water by a few degrees. Water, on the other hand, also provides large amounts of heat when it cools down.

The effect of this is most marked in the oceans, as they are large masses of water. They are warmed very slowly, but also retain the heat for a long time.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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.
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 8. OpenStax CNX. Sep 12, 2009 Download for free at http://cnx.org/content/col11050/1.1
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