JEE Main 2021PhysicsUnits and DimensionsMediumMCQ

JEE Main 2021 — Units and Dimensions Question with Solution

JEE Main 2021 (26 Feb Shift 1)

Question

In a typical combustion engine the workdone by a gas molecule is given by W=α2βe-βx2k T, where x is the displacement, k is the Boltzmann constant and T is the temperature. If α and β are constants, dimensions of α will be:

Choose an option

Show full solutionCorrect option: D
Correct answer
DM0LT0

Step-by-step explanation

kT  has dimension of energy

βx2kT is dimensionless

βL2=ML2T-2

β=MT-2

α2β has dimensions of work

α2MT-2=ML2T-2

α=M0LT0

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About this question

This is a previous-year question from JEE Main 2021, 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.