Question

Units of work done is ________.

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

Answer 1

The correct option is B $kg{m}^2{s}^{-2}$

Work done is given as the product of force and displacement along the force.
Unit of force is Newton.
$1N=1kgm/s^2$
Unit of Displacement is metre $\left(m\right)$.

Hence, unit of work is called Joule $\left(J\right)$:
$1J=1N\times 1m$
$1J=1kgm/s^2\times 1m$
$1J=1kg{m}^2/s^2$