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Natural sciences

Grade 4

Planet earth and the universe

Module 40

The earth and its movement

Activity:

Talking about the earth

[lo1.2]

THE BLUE SPHERE WE CALL HOME

  • This picture shows what the earth looks like from space. Space travellers tell us that the earth looks like a large, shining ball in the dark sky. It looks as if the surface of the earth is covered in clouds. The blue areas that we see are the oceans of our planet. The earth may seem small when we look at it from the moon, but if you had to dig through the middle of the earth to the other side, you would have to dig a tunnel of 6 400 km long!
  • The earth is the only planet on which life is possible, because it has a supply of air, water and soil. Only a quarter (approximately) of the earth’s surface is land, the rest is water in the form of the oceans, rivers, lakes, etc. The land consists of deserts, forests, grasslands, mountains and ice.

Divide the class into eight groups. You are going to make posters about this wonderful earth and put them up in the class. Use old magazines to make a collage on an A3 sheet of paper.

Group 1: Oceans

Oceans are made up of salt water and they cover a large part of the earth. Wind creates waves and keeps the water in motion all the time. The average depth of the ocean is 4 000 m. Plants and fish live even deep down in the sea.

Group 2: Deserts:

These are dry areas where it hardly ever rains. It is usually sandy, with rocks and stones here and there. There is very little water and therefore very few plants grow. The Sahara, in Africa, is the largest desert in the world.

Group 3: Polar Regions:

The Polar Regions are at the North and South Poles. They are covered in snow and ice and are the coldest places on earth.

Group 4: Grasslands:

These are relatively flat areas that receive very little rain. There are few trees, but many animals such as buck, zebras, giraffes, etc. live here. After rains have fallen there usually is much grass that can be eaten by the animals.

Group 5: Forests:

These are areas where trees grow very densely. Many animals and snakes and many types of birds and spiders are found in these forests.

Group 6: Rivers:

The longest river in the world is the Nile, which is approximately 6 671 km long. Rivers usually have their sources in mountains and may have waterfalls. Rivers usually have fresh water, sometimes fish are found in them and towns and factories are often developed alongside them. Rivers usually end at the sea and often form deltas where the river flows into the sea. Can you explain what a delta is?

Group 7: Mountains:

The highest mountain in the world is Mount Everest, which is 8 848 metres high. It is very cold on the highest peaks of such high mountains.

Group 8:Plant and animal life:

We find plants and animals everywhere on earth.

Activity:

Investigating and describing the movement of the earth

[lo 1.3, 2.1]

What causes day and night?

Use a ball and paste a map of South Africa on it. This ball represents the earth. You could also use a real globe. Use a torch to represent the sun. Spin the ‘earth’ to demonstrate the change from day to night. One full turn takes 24 hours (1 day). At the same time move the ‘earth’ around the ‘sun’ to demonstrate how the seasons come about. This takes 365¼ days (1 year).

Use the following key words to describe how day and night occur. Write a paragraph on the lines that are provided:

Key words: earth, spin, 24 hours, axis, sun, day, night

Assessment

LEARNING OUTCOME 1: SCIENTIFIC INVESTIGATIONSThe 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

We know this when the learner

  • leads investigations and collects data.

1.3 evaluates data and provides feedback on observations.

LEARNING OUTCOME 2 : CONSTRUCTING SCIENCE KNOWLEDGE The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard

We know this when the learner

2.1 recalls significant information.

Memorandum

This is a very pleasurable activity where learners learn to work together and to look at magazines with enquiring minds in order to find the right pictures for their collages. These can look beautiful in class or in a corridor.

Earth's movement

  • How do day and night happen?

Use the following key words to describe how day and night happen. Write a paragraph on the following lines:

Key words : earth, revolves, 24 hours, axis, sun, day, night

The earth revolves around its own axis every 24 hours . When any part of the earth faces the sun , it is day ; when it faces away from the sun , it is night .

Questions & Answers

what is math number
Tric Reply
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Sidiki Reply
Need help solving this problem (2/7)^-2
Simone Reply
x+2y-z=7
Sidiki
what is the coefficient of -4×
Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
Kala Reply
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
Moses Reply
12, 17, 22.... 25th term
Alexandra Reply
12, 17, 22.... 25th term
Akash
College algebra is really hard?
Shirleen Reply
Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table.
Carole
I'm 13 and I understand it great
AJ
I am 1 year old but I can do it! 1+1=2 proof very hard for me though.
Atone
hi
Adu
Not really they are just easy concepts which can be understood if you have great basics. I am 14 I understood them easily.
Vedant
find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
If f(x) = x-2 then, f(3) when 5f(x+1) 5((3-2)+1) 5(1+1) 5(2) 10
Augustine
how do they get the third part x = (32)5/4
kinnecy Reply
make 5/4 into a mixed number, make that a decimal, and then multiply 32 by the decimal 5/4 turns out to be
AJ
how
Sheref
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
hi
Ayuba
Hello
opoku
hi
Ali
greetings from Iran
Ali
salut. from Algeria
Bach
hi
Nharnhar
A soccer field is a rectangle 130 meters wide and 110 meters long. The coach asks players to run from one corner to the other corner diagonally across. What is that distance, to the nearest tenths place.
Kimberly Reply
Jeannette has $5 and $10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
August Reply
What is the expressiin for seven less than four times the number of nickels
Leonardo Reply
How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
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Source:  OpenStax, Natural sciences grade 4. OpenStax CNX. Sep 18, 2009 Download for free at http://cnx.org/content/col11096/1.1
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