<< Chapter < Page Chapter >> Page >

Natuurwetenskappe

Graad 5

Die aarde en die heelal

Module 25

Die atmosfeer

Aktiwiteit:

Om te kan verduidelik hoek die atmosfeer rondom die aarde lewe moontlik maak en hoekom ons dit in stand moet hou

[lu 2.1; 2.2]

Die planeet Aarde word deur ‘n kombers van gasse bedek wat ons die atmosfeer noem. Die dikte van die laag (atmosfeer) teenoor die grootte van die aarde, kan met die skil van ‘n lemoen teenoor die grootte van die lemoen vergelyk word.

Sonder die atmosfeer sou lewe op aarde nie moontlik wees nie. Dit bestaan nie alleen uit gasse wat noodsaaklik is vir lewe nie, maar verhoed ook dat ons deur die son “gebraai” of deur die koue van die buitenste ruim “verkluim” word. Die atmosfeer veroorsaak dat slegs die helfte van die son se strale die oppervlak van die aarde bereik.

Ons onderskei tussen vier lae in die atmosfeer .

Laag 1: die troposfeer

Hierdie is die laag teenaan die aardoppervlak. Dit is ongeveer 11 km dik en dit is in hierdie laag waar weerveranderinge in die lug plaasvind. Water kom feitlik uitsluitlik in hierdie laag voor.

Die lug in die troposfeer bestaan hoofsaaklik uit twee gasse: stikstof en suurstof. Daar is ‘n baie klein hoeveelheid ander gasse.

Jy kan die samestelling van die lug met ballonne voorstel:

Tel die ballonne en skryf die getalle neer:

Die met ‘n N (dit staan vir stikstof): _______________________________

Die met ‘n O (dit staan vir suurstof): _______________________________

Die met ‘n AG (dit staan vir ander): _______________________________

Beskryf nou in jou eie woorde hoe die lug in die troposfeer saamgestel is (die lug wat ons inasem):

Hoe hoër mens in die troposfeer opbeweeg, hoe “dunner” word die lug. Dit beteken die deeltjies is verder uitmekaar versprei. As jy byvoorbeeld op ‘n hoogte van 8 km ‘n houer met lug sou vul, sal daar minder deeltjies (stikstof, suurstof en ander gasse) in die houer wees as wanneer jy dit op die grond sou doen.

Laag 2: die stratosfeer

Die stratosfeer is ongeveer 40 km dik. Vliegtuie vlieg in hierdie laag. Die baie belangrike osoonlaag kom hier voor. Dit is ‘n tipe suurstoflaag wat die aarde teen die nadelige strale van die son beskerm. Sonder hierdie laag sal die meeste lewende wesens op aarde sterf. Die suurstof in die osoonlaag kom vanaf die plante wat op aarde groei. As hierdie balans versteur word deurdat minder suurstof die osoonlaag bereik en die plek daarvan deur ander gasse wat deur sekere menslike aktiwiteite vrygestel word opgeneem word, verander dit die temperatuur op aarde. Dit kan uiteindelik meebring dat dier en plant nie meer sal kan oorleef nie.

Laag 3: die mesosfeer

Hierdie laag is ongeveer 40 km dik en word gekenmerk deur temperatuurwisseling vanaf -113 grade Celsius tot by 440 grade Celsius (jou liggaamstemperatuur is 37 grade Celsius, water vries by ongeveer 0 grade Celsius en kook by ongeveer 100 grade Celsius). Vallende rotsstukke uit die buiteruim verbrand in hierdie laag en ons sien dit as “verskietende sterre”.

Laag 4: die ionosfeer (termosfeer)

Die ionosfeerlaag is ongeveer 350 km dik en bevat baie gelaaide deeltjies (ione) wat maak dat baie van die radioaktiwiteit wat by tye deur die son veroorsaak word, uitgeskakel word en nie ‘n effek op die aarde het nie.

Vrae:

1. Hoekom is dit belangrik dat ons plante plant eerder as om hulle uit te roei?

2. Industriële vooruitgang kan nadelig wees vir die natuur omdat dit die atmosfeer kan verander. Verduidelik hoekom.

3. Hoekom moet bergklimmers wat hoë berge soos Everest klim, suurstofmaskers dra?

Assessering

LU 2

KONSTRUKSIE VAN WETENSKAPKENNIS Die leerder ken, interpreteer en pas wetenskaplike, tegnologiese en omgewingskennis toe.

Dit is duidelik wanneer die leerder:

2.1 betekenisvolle inligting onthou;

2.2 inligting kategoriseer en eie reëls vir kategorisering verduidelik.

Memorandum

Getal ballonne (laat egter eers die leerders self tel):

  • N 79
  • O 20
  • AG 1

Samestelling: In elke 100 dele is daar 79 dele stikstof (79%), 20 dele suurstof (20 dele) en een deel ander gasse (1%)

Antwoorde:

L.W. Hierdie vrae moet spesifiek t.o.v. die atmosfeer beantwoord word.

  1. Plante gee suurstof en waterdamp af en neem koolstofdioksied op. So dra hulle by tot die handhawing van die nodige balans in die troposfeer en stratosfeer (insluitend die osoon)
  2. Enigiets wat na die osoonlaag verwys

3. Die druk raak so laag dat daar te min suurstof per volume eenheid is.

Questions & Answers

how environment affect demand and supply of commodity ?
Amos Reply
Wht at the criteria for market ?
Amos
what is difference between monitory policy and fiscal policy?
Malik Reply
monetary policy is a policy thrust by National Govt(CBN) to influence government spending, purchase &taxes
Frank
necessity of economics
Pamela Reply
I will say want,choice,opportunity cost,scarcity,scale of preference
Alao
what is monopoly market.How price output are determined under monopoly market
bisham
b) Monopoly market is an impecfect market where s single firm having the innovation to produce a particular commodity.Prices are determined through output since there are no other competitive.
Frank
Monopoly market:firm has market power & does not respond to market price
Frank
Explain the process of price determination under perfect competition market with suitable diagram
bisham Reply
Price determination under perfect competition via this process :firms have no market power to influence price rather firms respond to market price.
Frank
price is different from demand- demand is amount of commodity
Effah Reply
demand is amount /quantity of commodity a potential buyer is willing to buy at a given price at market
Frank
demand is a desire of customer on commodity with the ability to pay it and willing to buy it at given price of commodity
Harika
demand is price of what
Faith Reply
show that shortrun average cost
Baby Reply
what is economics
Mbah Reply
what is money
Mbah
what is money
Mbah
Difine macro economics
agaba
money is a medium of exchange between goods and services,maybe inform of currency.
Wesonga
Economics is study of how human beings strive to satisfy numerous wants using limited available resources.
Wesonga
how do you find the maximum number of workers the firms should employ order to produce where there are increasing returns
Jane
what are implications of computing national income?.
agaba
pl
MUDASIRU
what is the formulae for calculating national income
MUDASIRU
it calculated by value added method
Praveen
classify the production units like agriculture, banking, transport etc
Praveen
money is anything that is generally acceptetable for human
Ogbaji
Estimate the net value added(NVA) at fixed cost by each industrial structure
Praveen
definition of unemployment
Adam Reply
what are the causes of unemployment?
Mbubi Reply
The main causes of unemployment are listed below. 1. Frictional unemployment 2. Cyclical unemployment 3. Structural unemployment
assani
We can also categorize the causes on a broader sense as: 1. Political and 2. Social cause As unemployeement root causes are embaded in this two.
Yonathan
would opportunity cost exist if there was no scarcity?
assani
yes just because the opportunity cost arose when there is Alternative to choose among the alternatives.
BADAMASIU
I am thinking that, if our resources were unlimited, then there wouldn't be any need to forgo some wants. Hence the inexistence if opportunity cost
assani
Politics
Job
politics has done what?
assani
consider time assani
Mary
I'm Emmanuel,...I taught the main cause is the change in gov't.
Emmanuel
...Lack of capital to set up a firm respectively
Emmanuel
🙈
Emmanuel
I would like to bring in Educational levels can also be the cause the cause of the problem respectively
Emmanuel
I think the main causes of unemployment is lack of INFRASTRUCTURAL DEVELOPMENT OVER POPULATION OVER DEPENDENT ON GOVERNMENT LACK OF SELF EMPOWERMENT...
ananti
lack of skills among the new generation is the serious issue.
Vishal
Where I come from , I don't see why education or personal aspects seem to do with unimployment, technically the motivation and eigerness in all works of live is there , dispite the cultural influence and physical bearriors;the thing we lacking is Government Support and open market ethics.
Joe
sorry about that-(repation). We have a over powering ethical political system that's displacing the marketing asspects of economy and causing large scale unemployment right across the board...
Joe
can someone Explain Expansionary Monetary Policy and Contractionary Monetary Policy Using one of the instrument of Monetary Policy? Please am kinda lost here?. ta
Emmanuel Reply
using a graph show the case of substitute and compliment goods
Ade Reply
can anyone give me a simple explanation to Five Sector Macroeconomics?
Emmanuel
Can someone please define what economics is
jason Reply
economics simply is a social science subject that study human behavior.
dajan
economics is a social science which studies human behaviour as a relationship between ends and scarce means that has alternative uses
Alao
Can someone please tell me how to calculate GDP
Emmanuel
emmanual kapal to calculate GDP (Gross Domestic Product) has three method in calculating it (1)income approach (2) expenditure approach (3) value added method
Alao
thanks Alae
Emmanuel
u are welcome
Alao
in basic terms economics is revered to as battery system, it date back to when Men sees the need to exchange sapless goods and produce to gain , either wealth , basic necessities or to establish trading ties for personal benefit or social asspects in terms of coexistence and continuity, future .
Joe
what is the law of demand
Berlinda Reply
keep other thing constant, when the price increases demand decrease when the price decreases demand increases of the commodity.
sj
all things being equal,quantity demanded decrease as price increase and increase as price decrease
Seth
there's practial joke to it ..." the higher the demand ; scarcity, increase in production and drop in quality"... quite the controversy - for example China vs Europe, United States and we are all boxed up in between somewhere...
Joe
Other thing remain constant the low price of commodity the high quantity of commodity and vice versa is true
Baraka
Explain Effective demand
Anita Reply
What is effective demand
Anita
like Modi is in demand...best example of effective demand
Pranav
Don't get you
Anita
Anita you mean you don't get me or who?
Onyeking
level of demand that represents a real intention to purchase by people with the means to pay
Pranav
in a comparison of the stages of meiosis to the stage of mitosis, which stages are unique to meiosis and which stages have the same event in botg meiosis and mitosis
Leah Reply
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 5. OpenStax CNX. Sep 23, 2009 Download for free at http://cnx.org/content/col10980/1.2
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Natuurwetenskappe graad 5' conversation and receive update notifications?

Ask