Question

SI unit of G is $N{m}^2{kg}^{-2}$. Which of the following can also be used as the SI unit of G?

• A. $m^3{kg}^{-1}{s}^{-2}$
• B. $m^2{kg}^{-2}{s}^{-1}$
• C. $m{kg}^{-3}{s}^{-1}$
• D. $m^2{kg}^{-3}{s}^{-2}$

Answer 1

Answer: (A)

$m^3{kg}^{-1}{s}^{-2}$

Unit of $G$ is $N{m}^{2}k{g}^{-2}$ as $1N=kgm{s}^{-2}$.

So $G$ can be written as

$kgm{s}^{-2}\times m^{2}k{g}^{-2}=m^{3}k{g}^{-1}{s}^{-2}$