A, B, C and D are four different physical quantities having different dimensions. None of them is di

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1.Units, Dimensions and Measurement

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$A, B, C$ and $D$ are four different physical quantities having different dimensions. None of them is dimensionless. But we know that the equation $AD = C\, ln\, (BD)$ holds true. Then which of the combination is not a meaningful quantity ?

A

$\frac{C}{{BD}} - \frac{{A{D^2}}}{C}$

B

${A^2} - {B^2}{C^2}$

C

$\frac{A}{B} - C$

D

$\frac{{\left( {A - C} \right)}}{D}$

(JEE MAIN-2016)

Solution

Dimension of $A \ne $ dimension of $(C)$ Hence $A – C$ is not possible

Standard 11

Physics

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