Correct Answer - Option 2 : x = 1, y = -1, z = 1
CONCEPT:
Principle of homogeneity of dimensions:
-
According to this principle, a physical equation will be dimensionally correct if the dimensions of all
the terms occurring on both sides of the equation are the same.
- This principle is based on the fact that only the physical quantities of the same kind can be
added, subtracted, or compared.
- Thus, velocity can be added to velocity but not to force.
EXPLANATION:
Given that, P = pressure, Q = Energy striking per unit area per second, C = speed of light
Let k = PxQyCz....(1)
Dimensions of k = [M0L0T0]
Therefore Dimensions of \(Pressure=\frac{Force}{Area}=\frac{MLT^{-2}}{L^2}\) = ML-1T-2
\(Q=\frac{Energy}{Area \times time}=\frac{MLT^{-2}}{L^2}=\frac{ML^{2}T^{-2}}{L^{2}T}=MT^{-3}\)
\(C=LT^{-1}\)
Substituting these values in equation (1)
\(M^{0}L^{0}T^{0}=[ML^{-1}T^{-2}]^{x}[MT^{-3}]^{y}[LT^{-1}]^{z}\)
Applying the principle of homogeneity of dimensions, we get
x + y = 0...(i)
-x + z = 0...(ii)
-2x - 3y - z = 0...(iii)
solving (i),(ii),(iii), we get
x = 1,y = -1,z = 1
The correct x = 1,y = -1,z = 1