Question

If P, Q, R are physical quantities, having different dimensions, which of the following combinations can never be a meaningful quantity ?
A. `(P-Q)//R`
B. `PQ-R`
C. `PQ//R`
D. `(R+Q)//P`

Answer 1

Correct Answer - A::D
In this question, it is given that P,Q and R are having different dimensions, hence they cannot be added or subtracted, so we can say that (a) and `(e)`are not meaningful. We cannot say about the dimension of product of these quantities, hence (b),`(c)` and (d) may be meaningful.