JEE Mains · Physics · STD 11 - Units,dimensions and measurement
- JEE Mains 2021
- Hard
- MCQ
If force \(({F})\), length \(({L})\) and time \(({T})\) are taken as the fundamental quantities. Then what will be the dimension of density
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(\left[{FL}^{-4} {T}^{2}\right]\)
Step-by-step Solution
Detailed explanation
\(\text { Density }=\left[{F}^{{a}} {L}^{{b}} {T}^{{c}}\right]\)
\({\left[{ML}^{-3}\right]=\left[{M}^{{a}} {L}^{{a}} {T}^{-2 {a}} {L}^{{b}} {T}^{{c}}\right]}\)
\({\left[{M}^{1} {L}^{-3}\right]=\left[{M}^{{a}} {L}^{{a}+{b}} {T}^{-2 {a}+c}\right]}\)
\({a}=1 ; \quad {a}+{b}=-3 \quad ; \quad-2 {a}+{c}=0\)
\(\quad 1+{b}=-3 \quad {c}=2 {a}\)
\({b}=-4 \quad {c}=2\)
So, density \(=\left[{F}^{1} {L}^{-4} {T}^{2}\right]\)
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