How do Plants Breathe?

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Like any other living organism, plants also breathe. They take in oxygen and release carbon dioxide by the process of respiration. The oxygen taken in is used for breaking down sugars that the plant makes during photosynthesis, and energy and carbon dioxide are released. This energy is used by plant for its growth and reproduction. About 40 per cent of the energy released is used up and the rest is lost as heat.

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How do Aircrafts Fly?

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T o fly in the air, aircrafts need power, which is provided by the engines. They need a lift to rise from the ground and stay in the air. This lift is provided by the wings. The aircraft wings have a special shape called an aerofoil . The top surface of the wing is curved, while the bottom is flat. As the plane cuts through the air , the air that flows over the wing has to travel greater distances than the air flowing underneath the wing, so it has to travel faster over the top. This reduces the pressure above the wing and creates lift At take-off, the engine provides the power to generate lift. The forward thrust of the engines balances the resistance or drag set up by the air.
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Why is Venus so Hot?

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