Q.

The density of a material in SI units 128 kg m-3. In certain units in which the unit of length is 25 cm and the unit of mass is 50 g, the numerical value of density of the material is                                [2019]         

1 410  
2 640  
3 16  
4 40  

Ans.

(4)

Density ρ=ML3

           n1u1=n2u2

   128[M1L1-3]=n2[M2L2-3]

     n2=128[M1M2][L2L1]3    =128×[100050]×[25100]3

          =128×20×164=40