ρ=L3M
n1u1=n2u2
∴128[M1L1−3]=n2[M2L2−3]
∴n2=128×[M2M1][L1L2]3
=128×[501000]×[10025]3
=128×20×641
=40
JEE Main 2019 — Physics Mechanics
The density of a material in SI units is 128kgm−3. In certain units in which the unit of length is 25cm and the unit of mass is 50g, the numerical value of density of the material is:
Held on 10 Jan 2019 · Verified 6 Jul 2026.
410
16
40
640
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