Question

Which of the following is/are the unit(s) of density?

• A. $g{m}^{-2}$
• B. $gc{m}^{-3}$
• C. $kg{m}^{-3}$
• D. $kgc{m}^{-2}$

Answer 1

Answer: (B), (C)

$kg{m}^{-3}$

Density ($\rho$) of an object is the ratio of the object's mass($m$) to its volume ($V$).

$⟹\rho =\frac{m}{V}$

In SI system, unit of mass is kilogram ($kg$) and unit of volume is cubic metre ($m^3$), so the unit of density is kilogram per cubic metre $kg/m^3$ or $kg{m}^{-3}$.

In CGS system, unit of mass is gram ($g$) and unit of volume is cubic centimetre ($c{m}^3$), so unit of density is gram per cubic centimetre $g/{cm}^3$ or $g{cm}^{-3}$.