Question

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

• A. kinetic energy only
• B. work done only
• C. potential energy only
• D. all the above

Answer 1

Answer: (D)

all the above

Work done is same as energy which is measured in joules. 1 joule is same as 1 newton expanded over 1 meter which is force multiplied by distance.

Force is defined as mass into acceleration. Hence if we accelerate 1kg mass by 1m/s${}^2$ in a straight line for a distance of 1 meter, we have indirectly expanded 1 joule of energy .

Also acceleration is distance per second squared.

Thus we have (mass $\ast$ acceleration $\ast$ distance) which is Kg m${}^2$ S${}^{-2}$.