<< Chapter < Page Chapter >> Page >

Natuurwetenskappe

Energie-oordrag en kragte

Opvoeders afdeling

Memorandum

3. Flitslig van kamera - battery

4. Paraffienverwarmer paraffien

5. Gasverwarmer - gas

6. Haardroër - elektrisiteit

7. Windmeul - wind, ens.

Leerder afdeling

Inhoud

Aktiwiteit: om die energiebronne van alledaagse items te identifiseer [lu 1.2]

Dink aan items in julle huise en aan dinge wat beweeg, en doen dan die volgende saam met ‘n maat. Probeer om die lys te voltooi:

ITEM BRON VAN ENERGIE
motor petrol / diesel
trein elektrisiteit / steenkool
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________
_______________________________ _______________________________

3. Brandstowwe

Die plante en diere wat miljoene jare gelede gelewe het, het die son se energie geabsorbeer terwyl hulle gegroei het. Hulle is begrawe onder rotslae wat mettertyd oor hulle gevorm het. Hulle oorblyfsels is geleidelik deur verskillende chemiese reaksies in olie, steenkool en gasse verander. Ons noem hierdie brandstowwe fossielbrandstowwe . Olie, steenkool en gasse is nie-hernubaar , d.w.s. hulle kan nie vervang word nie. Daarbenewens moet hulle uit ondergrondse reserwes gemyn word en hul verbranding doen skade aan ons omgewing en ons gesondheid. Een nie-hernubare energiebron wat nie ‘n fossielbrandstof is nie, is kernkrag . Sekere metale soos uraan ondergaan ‘n proses wat ons kernsplitsing noem en stel dan groot hoeveelhede energie vry. Kernkrag word bv. by die kernkragstasie by Koeberg gebruik om elektrisiteit op te wek wat deur die inwoners van Kaapstad gebruik word. ‘n Klein hoeveelheid kernkrag lewer groot hoeveelhede kernbrandstof en veroorsaak baie min omgewingsbesoedeling. Daar is ook tans groot hoeveelhede kernbrandstof beskikbaar. Kernkragsentrales moet naby die kus gebou word as gevolg van die behoefte aan waterverkoeling. Dit bring mee dat die energie soms oor lang afstande vervoer moet word. Radioaktiewe bestraling kan lei tot gesondheidsgevare en dit neem honderde jare voordat radioaktiewe kernafvalprodukte nie meer radioaktief is nie en moet dus vir baie jare in spesiale houers ondergronds geberg word. Kernkrag veroorsaak egter nie suurreën of die kweekhuiseffek soos fossielbrandstowwe nie.

Omdat hierdie nie-hernubare brandstowwe nie meer vir baie lank beskikbaar gaan wees nie, moet ons energie bespaar en van alternatiewe energiebronne soos die son, water, wind, golwe, getye en biogasse begin gebruik maak vir ons krag. Groot vordering is reeds op hierdie gebied gemaak.

Assessering

Leeruitkomste 1: Die leerder is in staat om met selfvertroue op weetgierigheid oor natuurlike verskynsels te reageer, en om binne die konteks van wetenskap, tegnologie en die omgewing verbande te ondersoek en probleme op te los.

Assesseringstandaard 1.2: Dit is duidelik wanneer die leerder ondersoeke uitvoer en data versamel: organiseer en gebruik toerusting of bronne om inligting in te versamel en aan te teken

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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Good
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Natuurwetenskappe graad 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11078/1.1
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Natuurwetenskappe graad 7' conversation and receive update notifications?

Ask