Question

Derive S.I. unit of Joule (J) in terms of fundamental units.

Answer 1

Joule is a unit of work.

Now by using the formula of work done 

W = F s(F = force and s = displacement)
= Mas    (a = acceleration)
= Msv/t   (v = velocity  and t = time)
=Ms s/t^​2 (as velocity is displacement /time)
W = M s²/t²

hence the above formula is in form of its fundamental units like mass, time and length and the dimension formula of joule = ML²T^-2