Question

Which of these physical quantities has base units kgm²s^-2?

A. Pressure B. Energy C. Power D. Momentum

Answer 1

$${\rm[Pressure]=N/m^2=(kg\cdot m/s^2)/m^2}\\ \rm=kg\cdot m^{-1}\cdot s^{-2}$$

$${\rm[Energy]=J=N\cdot m=(kg\cdot m/s^2)\cdot m}\\ \rm=kg\cdot m^{2}\cdot s^{-2}$$

$${\rm[Power]=J/s=N\cdot m/s=(kg\cdot m/s^2)\cdot m/s}\\ \rm=kg\cdot m^{2}\cdot s^{-3}$$

$$\rm[Momentum]=kg\cdot m/s=kg\cdot m\cdot s^{-1}$$

Answer: B. Energy