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How does the Secretary bird catch snakes?

The Secretary bird prefer to walk around looking for its prey rather than to fly. As a result its feet are less adapted for killing. The Secretary bird strides around African grasslands on its long legs hoping to disturb its prey. It catches insects, small mammals and lizards, but it is best known for eating snakes. It attacks a snake …

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How does the sea from a ‘below hole’?

In stormy weather, powerful waves hurl loose rocks at the shore, undercutting cliffs. While soft rocks are worn back to form bays, hard often survive as headlands in which waves then hollow out caves. If the roof of a cave collapses, a ‘blow hole’ is formed in the ground above. When waves break in the cave, clouds of spray burst …

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How does the sea create new land?

Most people are familiar with the idea of the sea eroding or destroying land. For example, storm waves can remove rock from many coasts. Some loose rock is swept out to sea, but some is moved along the shore. Groynes, or sea walls, which jut out from the coast in many resorts, are built because of this movement. Without them, …

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How does the hybrid engine work?

Hybrid engines use two or more power sources. They consist of a usual fuel engine, complemented by a pollution-free engine, an electric engine for example. The fuel engine and brakes are used to recharge the batteries for the electric engine, eliminating the need to plug in while unused. When brakes are applied, some of the energy being used to stop …

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How Does Satellite TV Work?

Nine ‘o’ clock. It’s time for your favourite serial on television. Have you ever wondered how the same serial can be viewed by millions of people across the world? This is possible because of satellite television technology. It uses man-made or artificial satellites to send your favourite serial to your television set. But why do we need satellites for this …

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How does frost split rocks?

Frost is frozen moisture. It forms when invisible water vapour in the air changes directly from a gas-like state into ice crystals. In mountains, moisture in cracks in rocks freezes at night. Because ice occupies more space than water, the ice exerts a wedge like pressure inside the cracks, widening them until the rocks split. This is called frost action.

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How does calcium carbide ripen mangoes?

For reasons of safe transportation of fruits, mangoes, bananas etc are picked before they ripen fully. Slightly green harvested mangoes are subjected to small containers of calcium carbide (CaC2) with a plastic covering. CaC2 reacts with the moisture in the air to release acetylene (or ethyne) gas, which like ethyleneis – a chemical substance produced by fruits to accelerate the …

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