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Being out of doors on a windy day can make us feel energetic. There are many ways in which we can enjoy the wind.
Form groups and take a minute to think about the nicest way in which one could enjoy the wind.
When groups report back, decide which idea will be the cheapest to follow, and which will be the most expensive.
Which group’s idea will require the least effort, and which will require the most effort?
Write labels for the following pictures.
Plants also make use of the wind!
Wind disperses the seeds of plants and trees. Plants that use the wind in this way have very light seeds.
Interesting facts: Some seeds have wings that help them to “fly”.
Other seeds glide like parachutes.
The feathers of birds help them to glide on the wind. If the wind is strong, birds are assisted to fly for hundreds of kilometres when they migrate to other countries.
Some animals, rabbits for instance, sniff the air when they are eating. Because the wind carries the smell of their enemies, they are warned of danger.
The pilot of an aeroplane depends on the windsock at the airport so that he or she can determine from which direction for taking off or landing. The windsock also indicates the direction of the wind.
LEARNING OUTCOME 1 : SCIENTIFIC INVESTIGATIONS The 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.
We know this when the learner
LEARNING OUTCOME 3 : SCIENCE, SOCIETY AND THE ENVIRONMENT
We know this when the learner
If one is out of doors on a windy day, one can feel very energetic. There are many ways in which one can enjoy the wind.
One can participate in water sports.
One can fly in a glider!
One can fly a kite.
Let us think of conditions when the wind could be dangerous
1. Trees can be uprooted, they can destroy motor cars and houses, roads can be blocked, power lines can be blown down and homes can be left without electricity.
2. Storms at sea can cause flooding on land, and ships can be wrecked.
3. Tornadoes are the strongest kind of wind-storms and can have a velocity (speed) of up to 300 km per hour. A tornado can cause incredible damage.
4. Wind can cause soil erosion. Think of ways in which it can be prevented.
5. If the wind blows from one direction all the time, trees can grow skew. How can we live safely in such conditions?
6. If a veld fire occurs, wind can make it worse and massive plantations can be destroyed.
7. Breakwaters can be built along the coast to prevent the water from flooding the land.
8. Some animals live safely in their underground tunnels.
9. In dangerous places bridges and roads are closed temporarily so that motorists will not travel there.
10. Rows of trees and hedges can be planted along cultivated fields to prevent the crops from being damaged.
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