Question

why do we have different units for the same physical quantity??​

Answer 1

Answer:

Because body differ in order of magnitude significantly in respect to the same physical quantity.

Explanation:

For example: interatomic distance are of the order of angstroms, inter-City distance are of the order of km, and interstellar distances are of the order of the light energy.

Answer 2

Answer:-

We have different units for same physical quantity because these units were used in different parts of the world.