what is the significance of specific gravity determination?

Answer 1

Relative density or specific gravity. It gives the mass per unit volume of a substance to that of water which is 1. This idea was used by Archemedis in determining whether the crown of the king was actually adultrated or not. He sunk the crown in water collected the volume over flowed which gave the volume of the crown. He weighed the crown. Divided mass by volume to get the density of gold in the crown. If this was different from that of gold then the crown might have been adultrated. The story goes that the crown was not tampered by the crown maker with the gold given by the King.

Answer 2

Specific Gravity or SG is pretty handy. In the oilfield for example it is used to calculate the pressure exerted by a column of drilling fluid on the wellbore. This is the force that prevents nasties such as gas coming in from the formation this in turn avoids "kicks" which can be real bad news. You can figure this out using - SG(density) X gravity (9.81) x vertical depth of the well. It is also handy for environmental reasons, in that you can calculate the weight of any fluid in Kg Tonnes or whatever. This is then used to report the exact weight of chemicals or fluids discharged to the sea under a licensing system.

Answer 3

It gives a relative density to a reference material (usually water).

Typical sp. gr. are a very quick way of determining if something will float (assuming sp. gr. ref material is water). 1 is bouyant, higher sinks, lower floats.