The specific gravity of an object is the ratio between the density of an object to a reference liquid. Usually, this reference liquid is water, which has a density of 1 g/mL or 1 g/cm3.
Water has a specific gravity equal to 1. Materials with a specific gravity less than 1 are less dense than water, and will float on the pure liquid; substances with a specific gravity more than 1 are more dense than water, and will sink.
The ice and steam point have values 32 F and 212 F respectively, on the Fahrenheit scale. Corresponding values on the Centigrade scale are
A base quantity is chosen and arbitrarily defined, rather than being derived from a combination of other physical quantities. The 7 base quantities are:
PHYSICAL QUANTITY | BASE SI UNIT |
---|---|
Mass (m) | Kilogram (Kg) |
Length (ll) | Metre (m) |
Time (t) | Second (s) |
Current (II) | Ampere (A) |
Temperature (T) | Kelvin (K) |
Amount of sub. (n) | Molar (mol) |
Luminous Intensity (L) | Candela (cd |