JEE Main 2021 — Units and Dimensions Question with Solution
JEE Main 2021 (27 Aug Shift 1)
Question
Which of the following is not a dimensionless quantity?
Choose an option
Show full solutionCorrect option: C
Correct answer
CPermeability of free space
Step-by-step explanation
The power factor is defined as, which is dimensionless, the formula of quality factor, , which is also dimensionless, and the permeability in free space, , but permeability in free space is defined as, , here is the speed of light in vacuum and is the permittivity in free space so this having dimension.
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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.