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Can continents drift?

If you look at a map of the Atlantic Ocean, you will see that the coastal shapes of the Americas resemble those of Europe and Africa. Might these continents have once been joined together like pieces in a giant jigsaw? A German meteorologist, Alfred Wegener (1880-1930), thought so. He wrote a book saying that, about 200 million years ago, all …

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Can babies really be born in test-tubes?

We hear a lot about ‘test-tube’ babies. These babies are not, in fact, born in a test-tube, but they do begin life in one. Medicine can sometimes help people who cannot have children. Normally, a new life begins in the mother’s womb when a sperm cell from the father fertilizes an egg cell from the mother. The two cells fuse …

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Can a scorpion kill a man?

Scorpion are particularly ferocious animals, even to each other, and so they lead solitary lives. They live in dry warm, areas of the world and in the wild hide themselves away in dark places, under logs or stones, for example, waiting for their prey. This normally consists of small insects and spiders. As scorpion cannot see very well they rely …

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At what speed does electricity travel compared to light?

Electrical fields in theory do transmit at the speed of light. In real systems, wires have capacitance and other effects that slow the propagation. Typical propagation speeds are 0.3 to 0.7 times the speed of light, depending mostly on the wire shape and size, characteristics of wire insulation, and interactions with other conductors.

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Are there people on Mars?

Percival Lowell, an American astronomer, thought he saw canals criss-crossing the deserts of Mars, when he observed the planet though his telescope early this century. He believed that these canals were built by a Martian civilization to bring water for irrigation from the planet’s polar caps. However, space probes have shown that the canals were simply optical illusions, and that …

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Anyone for the shuttle?

When the first manned satellites went into space in the early 1960s, many people felt that the wildest dreams of science fiction writers were coming true. It was only about 50 years earlier that the first aeroplanes had flown. What amazing progress had been made in half a century! But in the next 20 years events moved still faster In …

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Amazing facts about animals

Amazing facts about animals — A captive, great brown bear of Alaska, a close relative of the fabled grizzly bear, weigh about 650 kilograms! The female Emperor penguin comes to the land, lays one egg on bare ice, then immediately returns to the ocean. The male keeps the egg warm for two months until it hatches, by rolling it onto …

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