$$A,B,C$$ and $$D$$ are four different physical quantities having different dimensions. None of them is dimensionless. But we know that the equation $$AD = C\,\ln \,\left( {BD} \right)$$ 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.
$$\frac{{\left( {A - C} \right)}}{D}$$
Answer :
$$\frac{{\left( {A - C} \right)}}{D}$$
Solution :
Dimension of $$A \ne $$ dimension of $$\left( C \right)$$
Hence $$A - C$$ is not possible.
Releted MCQ Question on Basic Physics >> Unit and Measurement
Releted Question 1
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