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How many are weighed by Earth

Рефераты по астрономии » How many are weighed by Earth

Because Earth is suspended in space, to «weigh» her – quite

not the same that to lay an object on the bowl of scales. When we speak about weight of Earth, we mean the amount of matter, from

which she is. It is named mass.

Mass of Earth - about 5,976 sekstyllyonov tons. That you

could evidently to imagine, as this number looks, here it:

5 976 000 000 000 000 000 000. How scientists counted up, that mass

Earths just the same.

To do it, they used the principle, based on that two bodies are attracted to each other. Force of gravitation depends on it. Simpler speaking, the law of gravitation says, that two bodies are attracted to each other with force, which depends on their mass and distance between them. Than anymore objects. That znachy-tel'nye force which attracts them to each other. Than farther from each other they are that these force less.

To measure weight of Earth, it is needed to do the following: little

gruz to hang up on a filament, after measure exact position of this load. Then the ton of lead is necessary to be disposed next to the suspended load. Between him and attraction is a lead, as a result

which a load hardly otklanyaetsya aside (in actual fact this declination makes less than 0, 000 02 mm, that you see, as far as measuring must be exact).

After these measuring scientists can by mathematics

to calculate weight of Earth.