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Natural sciences

Grade 4

Planet earth and the universe

Module 45

Stormy weather

Activity:

Learning about stormy weather conditions

[lo 2.1, 3.1]

Stormy weather

:

What do you do when the weather is stormy? Tell the class about funny stories related to storms.

Dark clouds converge in the air. Heavy rains fall to the earth. Now and again there is a bright flash of lightning and we hear the roar of thunder. But what is actually happening?

Clouds:

The air is full of small dust particles. Water drops form around such dust particles and then form clouds together with millions of other drops.

Try the following:

Mark an empty bottle in mm and place it outside when it rains.

Lightning:

During a storm strong winds blow the small water drops that have formed around the dust particles, into the centre of the clouds where they bounce against each other. Each of the small particles of a cloud has either a positive or negative electrical charge. When the particles bump against each other the charges separate. The majority of the positive charges move to the top of the cloud and the negative charges move toward the bottom of the cloud. Lightning is a massive electrical spark in the cloud. This spark occurs when the negative charges in one cloud come into contact with the positive charges in another cloud or with the ground.

Thunder

Thunder is the loud noise that you hear when warm air and cold air suddenly come together. When lightning brightens the sky, it also heats the surrounding air. When this hot air comes into contact with the cold air, a gigantic wave of moving air causes the clap of thunder.

Dangerous weather

Tornado

This is a very strong wind that is caused when a front with cold and dry air comes into contact with warm, moist air. It causes a large black cloud in the air. The warm air rises rapidly and more warm air moves in below it to replace it. Sometimes the rising air begins to move in a spiral and a tornado develops. If a tornado reaches the ground, it causes incredible damage because it sucks up everything that it encounters on the ground into the air.

Hurricane

This is a very big storm that starts on the surface of tropical seas. It consists of a large quantity of wind and rain that begins to spin around its centre, which we call the “eye”. It moves forwards as it rotates and creates enormous waves that are very destructive.

Cut A4 sheets of paper into four (into quarters) to have one small sheet of paper for each learner in the class. Each learner must draw an aspect of the weather on his or her piece of paper. Work clearly and neatly. Stretch a washing line across the classroom and hang the drawings of the “weather conditions” from the line!

Assessment

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.

LEARNING OUTCOME 3 : SCIENCE, SOCIETY AND THE ENVIRONMENT The learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.

Assessment Standard

We know this when the learner

3.1 understands science and technology in the context of history and personal knowledge.

Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
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John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
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David Reply
what is viscosity?
David
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emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
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Muhammad Reply
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Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir 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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