JEE Main 2021PhysicsUnits and DimensionsMediumMCQ

JEE Main 2021 — Units and Dimensions Question with Solution

JEE Main 2021 (20 Jul Shift 2)

Question

If time t, velocity v, and angular momentum l are taken as the fundamental units. Then the dimension of mass (m) in terms of t, v and l is:

Choose an option

Show full solutionCorrect option: D
Correct answer
Dt-1v-2l1

Step-by-step explanation

m∝tavbℓc

m∝[T]aLT-1bML2 T-1c

M1 L0 T0=McLb+2cTa-b-c

Comparing powers, 

c=1, b=-2, a=-1

m∝t-1v-2ℓ1

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Units and Dimensions chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

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.