What is the SI unit of specific gravity

Question

Question

This question was previously asked in

JKSSB JE Civil Jal Shakti 6 Dec 2022 Official Paper (Shift 2)

Answer 1

Explanation:

Specific gravity: It is also known as relative density, it is the ratio between the density of an object and a reference substance.
- The specific gravity can tell us, based on its value, if the object will sink or float in our reference substance.
- Mathematically it is Specific gravity = Density of substance/density of water.
- It has no dimension.
- Usually, our reference substance is water which always has a density of 1 gram per milliliter or 1 gram per cubic centimeter or 1000 kg /m3.
From the above, it is clear that specific gravity has no dimension. Therefore option 4 is correct.

Additional Information

Density: It is defined as the mass of a body per unit volume. We can also say how much mass it can contain in a specific volume.
- As of dense material like Iron takes more mass in a given volume than of wood.
- Mathematically it gives a formula Density (ρ) = mass (m) / Volume (V)
- SI Unit is kg/m3.
- 1m3 = 1000 liters of water.