Question

What is Relative density?

Answer 1

Relative density of a substance is the ratio of the mass of any volume of the substance to the mass of an equal volume of water.

Relative density doesn't have any SI unit.

And formula for relative density :

Relative density of a substance = Density of substance / density of water

HOPE it helps u

Answer 2

Relative density is given by the density of a substance by density of water at 4 degree Celsius.
It is defined as the ratio of a substance 's density to water's density at 4 degree Celsius. It is also known as specific gravity.
Since it's a ratio there's no specific units for it.
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