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Where do Volcanoes occur?

We know that the Earth’s crust and the top part of the mantle are split into rigid sections, called plates, which are up to 70-100 km (43-62 miles) thick. Beneath the plates, temperatures are high and the rocks are semi-molten. Currents in the molten material are moving the plates about. Plates are moving apart along the ocean ridges. When they …

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Where do spacecraft get their power?

Spacecraft cannot carry large supplies of fuel and these aren’t any filling station in space. Instead, many have large panels of solar cells. These capture sunlight and turn it into electricity. The sun always shines in space, so there is always electricity to power the spacecraft. Some space probes travel to the outer planets far from the Sun. There the …

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Where do sounds of heartbeat come from?

The first sound you hear, the one which says ‘lub’ is caused by the rapid closure of the valve between the auricles and the ventricles (auriculo-ventricular valves). This sound, rather like a door closing, is accompanied by a dull murmur, caused by the contraction of the ventricular muscles. The second sound is caused by the closing of the arterial valves. …

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Where do dreams go when you wake up?

The simple answer is either they are stored in your memory or you forget them. But this question makes us ask a great number of other question. What is the difference between day-dreaming and the dreams we have when we are asleep? Can dreams foretell the future? How long do they really last? Do we have dreams in color or …

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Where do butterflies lay their eggs?

Butterflies, and moths as well for that matter, are very particular about laying their eggs. Most butterflies leave them on only one sort of plant because this is the plant that the newly hatched larvae, called caterpillars, will feed on. So the female butterfly will spend some time finding the correct plant (the foodplant) before laying her eggs. You might …

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Where do bath sponges come from?

The sponge with which some people regularly soap themselves in the bath is really the skeleton of a particular type of natural sponge. Bath sponges are supported by a framework of a resilient, elastic material called ‘spongin’, and it is this that makes up the bathroom sponge. Bath sponges are found in warm shallow seas, and in various part of …

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Where did the French first settle in America?

One of the reasons why the French wished to establish colonies in the New World was because some of them wanted to escape religious persecution at home. In 1562, a group of thirty French Protestants, let by Jean Ribault, landed at the mouth of the St John’s River in the Spanish territory of Florida (left). However, the Indians were hostile, …

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Where did Shoes come from?

Ooh, aah, ouch! People in ancient times must have yelped like this when they walked on rough ground without any shoes on. And it was probably the pain and discomfort that propelled them to cover their feet for protection. Footwear has a history which goes back many thousands of years, and has long been an article of prestige for people …

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