The unit of density in SI system is kgm−3 . From the dimensional analysis method, both densities should have the same amounts. Let the value of the density in standard units is x , then we can write, 0.5cm3gm=xm3kg 10−60.5×10−3kg/m3=xkg/m3 x=10−60.5×10−3=500
In terms of N , we have x=5×102 , so N=5 .