Question

$kg{m}^2{s}^{-2}$ is the unit of

• A. Force
• B. Energy
• C. Power
• D. momemtum

Answer 1

The correct option is B

Energy

The explanation for the correct option:

Option B:

1. Energy $E=mgh$( Potential energy) where m=mass represented by $\left(kg\right)$, g = acceleration due to gravity $\left(m{s}^{-2}\right)$ and s = height $\left(m\right)$
2. Hence, the dimensional unit of energy, $E=kg\times m{s}^{-2}\times m=kg{m}^2{s}^{-2}$.

The explanation for the incorrect options:

Option A: The dimensional formula of force is $kgm{s}^{-2}$

Option C: The dimensional formula of power is $kg{m}^2{s}^{-3}$

Option D: The dimensional formula of momentum is $kgm{s}^{-1}$.

Hence, the correct answer is Option B.