JEE Main 2019PhysicsUnits and DimensionsEasyMCQ

JEE Main 2019 — Units and Dimensions Question with Solution

JEE Main 2019 (10 Jan Shift 1)

Question

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

Choose an option

Show full solutionCorrect option: C
Correct answer
C40

Step-by-step explanation

ρ=ML3

n1u1=n2u2

∴128M1L1-3=n2M2L2-3

∴n2=128×M1M2L2L13

 =128×100050×251003

=128×20×164

=40

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About this question

This is a previous-year question from JEE Main 2019, covering the Units and Dimensions chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.