Antiquity. Hydrostatics questions

you are: Antiquity

It is necessary to mention its works devoted to questions of a hydrostatics also.

Who from us does not remember Archimedes known law that ' on any body shipped in a liquid, the pushing out force directed upwards and equal weight of a liquid superseded by it ' operates. Archimedes has given some more formulations of this law in which all other cases are provided:

1) if the weight of a body is less than weight of the WATER superseded by IT, a body plunges Into WATER partially, superseding only such quantity of water which weight is equal to body weight; in this case the body floats on water;

2) if the body weight is equal to weight of the water superseded by it the body freely floats in water;

3) and, at last, if weight of a body more than the water superseded by it, the body sinks in water.

There is the popular parable connected with opening of this law. It is said that sirakuzsky tsar Gieron has asked once Archimedes to check up, whether the goldsmith of silver to the gold crown made by it by request of the tsar has added. Archimedes long thought how to execute desire of the tsar while once, sitting in a bath, has felt, as in process of immersing in water its body becomes easier, and has suddenly opened that is called now as Archimedes law. Stunned with opening, Archimedes as if has jumped out of a bath and with shout ' Eureka! ' (' Has found! ') naked has run out on street. On the basis of this law, Archimedes could define easily, whether there is in gold of a crown a silver impurity. Was to compare relative density of a crown to relative density of gold enough to establish not only impurity presence, but also quantity of silver in a crown.

As it is known, Archimedes posesses words: ' Give me a point of support, and I will shift the Earth '. It has been told concerning building by order of Gierona of the magnificent three-mast ship whom, however, workers could not float so it is heavy there was this ship. Archimedes has easily solved a problem by means of system of the blocks established on a land in some distance from the ship.