\(v\) = velocity = \([L{T^{ - 1}}]\),
\(\rho\) = density = \([M{L^{ - 3}}]\),
\(g\) = acceleration\ due\ to\ gravity =\([LT^{-2}] \)
\(m = K\,\frac{{\rho \,{v^6}}}{{{g^3}}}\) \( \Rightarrow \,[M] = \frac{{[M{L^{ - 3}}]{{[L{T^{ - 1}}]}^6}}}{{{{[L{T^{ - 2}}]}^3}}} = [M]\)
\(L.H.S. = R.H.S.\)