Q14 of 44 Page 7

If P, Q, R are physical quantities, having different dimensions, which of the following combinations can never be a meaningful quantity?

Given,


P, Q, R have different dimensions.


From dimensional analysis we know that physical quantities having different dimensions cannot be added or subtracted.


From the above arguments we can conclude that, the combinations in option (a) and (e) are not dimensionally possible.


On the other hand,


In option (b) the product of P and Q may result into dimension of R.


Option (c) is also dimensionally possible as physical quantities with different dimensions can multiplied or divided.


In option (d) the product of P and R may result into dimension of Q2.

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