Which one of the foilowing pairs does not have the same dimension?

Options

A. potential energy and kinetic energy
B. Density and specific gravity
C. Focal length and height
D. Gravitational force and frictional force

Answer

B

Explanation

Specific gravity or relative density
`=("density of body")/("density of water")`
So, it has neither unit nor dimension,
while density `=(mass)/(volume)=([M])/([L^(3)])=[ML^(-3)]`