Do you know why does the wind blow?

Prof. Know Why answers:

What is wind? Why does the wind blow? How is wind different from air? Did any of these questions ever struck your mind? - If yes, just read on.

Wind is moving air and is caused by differences in air pressure within our atmosphere. Air, under high pressure, moves to the areas of low pressure. The greater the difference in pressure, the faster the air flows, and the stronger is the wind of that place. –That’s the simple explanation.

The atmosphere is composed of air which, is made up of tiny particles of different gases like nitrogen, hydrogen, oxygen, etc. The Sun shines on our atmosphere all the time. But, it heats the surface of the Earth unevenly. As a result, it’s warm in some places, while cold in other places. When air gets warmer, its particles spread out. This makes the air lighter, or less dense. So it rises. When air cools, it becomes heavier, or denser, and sinks. As warm air rises, air from cooler areas flows in to take the place of the heated air. This process is called convection and causes air to move. The differential heating of the Earth's surface and the resulting convection is what causes wind on this planet.

Have you ever wondered, how a hot air balloon floats in the air? Well, it applies the same science as that of the wind. Air is heated by a gas flame below the balloon. The air inside becomes hot and lighter or less dense than the cooler air outside the balloon. As the hot air rises, it carries the balloon upward. When the gas flame is turned down, the air cools and the balloon sinks back to the ground.

Wind also plays an important role in determining weather conditions.

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Do you know why sea water is salty?

Prof. Know Why answers:

Why and how is the sea water salty? Well, to put it simple, - rivers erode minerals from rocks and soil throughout their journey and finally deposit them into seas. These elements include sodium and chlorides, which, when combined, become salt.

For a bigger picture, the sea water is salty because of the gradual concentration of dissolved chemicals eroded from the Earth's crust is dumped into the sea. Furthermore, solid and gaseous ejections from volcanoes under the sea, suspended particles that are swept to the ocean from the land by onshore winds, and materials dissolved from sediments deposited on the ocean floor also contribute to its saltiness.

Salinity is increased by evaporation or by freezing of sea ice and it is decreased as a result of rainfall, runoff, or the melting of ice.

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Do you know why dark chocolates are beneficial?

Prof. Know Why answers:

Chocolates are always yummy, delicious and irresistible, especially with girls and kids. And now, they also seem to be beneficial for your health because a daily dose of yummy dark chocolate may help patients suffering from the chronic fatigue syndrome (CFS).

Serotonin (a brain chemical related to CFS) is believed to play an important role in the regulation of anger, aggression, body temperature, mood, sleep, vomiting, appetite and fatigue. According to scientists from Hull York Medical School, dark chocolates have been found to lower levels of serotonin. The research team said that patients with CFS, found that their symptoms were reduced when they consumed dark chocolate, much more so when they consumed milk chocolate that had brown dye added to it. The researchers noted that patients taking dark chocolate reported significantly less fatigue when they started eating the sweet. They also reported more fatigue when they stopped eating it. The scientists, however, stressed that the quantity of dark chocolate consumed should be moderate.

Endocrinologists say, dark chocolate is high in polyphenols, which have been associated with health benefits, like reduction in blood pressure. Also, high polyphenols appear to improve levels of serotonin in the brain , which has been linked with CFS.

According to doctors and nutritionists, cocoa is rich in antioxidant properties and so consuming dark chocolate can over stimulate the nervous system, helping reducing fatigue.

So cheer up all you girls and chocolate lovers – now you have reasons to gorge on your favorite dark chocolates.

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