JEE Mains · Physics · STD 11 - Units,dimensions and measurement
- JEE Mains 2021
- Hard
- MCQ
Which of the following is not a dimensionless quantity?
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) Permeability of free space \(\left(\mu_{0}\right)\)
Step-by-step Solution
Detailed explanation
\(\left[\mu_{{}}\right]=1 \text { as } \mu_{{r}}=\frac{\mu}{\mu_{{m}}}\)
[power factor \((\cos \phi)]=1\)
\(\mu_T{0}=\frac{{B}_{0}}{{H}}\left(\right.\) unit \(\left.={NA}^{-2}\right)\) : Not dimensionless
\(\left[\mu_{0}\right]=\left[{MLT}^{-2} {A}^{-2}\right]\)
quality factor (Q) \(=\frac{\text { Energystored }}{\text { Energy dissipated per cycle }}\)
So \(Q\) is unitless \(\&\) dimensionless.
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