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If $$E$$, $$L$$, $$M$$ and $$G$$ denote the quantities as energy, angular momentum, mass and constant of gravitation respectively, then the dimensions of $$P$$ in the formula $$P = EL^2M^{-5}G^{-2}$$ are:
We have to find the dimensions of the physical quantity $$P$$ defined through the relation
$$P = E\,L^{\,2}M^{-5}G^{-2}.$$
Here the symbols represent the following physical quantities:
Energy ⇒ $$E$$ with dimensional formula $$[E]=[ML^{2}T^{-2}]$$
Angular momentum ⇒ $$L$$ with dimensional formula $$[L]=[ML^{2}T^{-1}]$$ (because angular momentum is the product of moment of inertia $$\bigl[ML^{2}\bigr]$$ and angular velocity $$[T^{-1}]$$)
Mass ⇒ $$M$$ with dimensional formula $$[M]=[M^{1}]$$
Gravitational constant ⇒ $$G$$ with dimensional formula $$[G]=[M^{-1}L^{3}T^{-2}]$$ (this follows from Newton’s law $$F = G\frac{m_{1}m_{2}}{r^{2}}$$)
Now we substitute these dimensional expressions into the formula for $$P$$.
First, write the overall dimensional product:
$$[P]=[E]\,[L]^{2}[M]^{-5}[G]^{-2}.$$
Substituting each individual dimension we get
$$[P]=\bigl[ML^{2}T^{-2}\bigr]\;\bigl[ML^{2}T^{-1}\bigr]^{2}\;\bigl[M\bigr]^{-5}\;\bigl[M^{-1}L^{3}T^{-2}\bigr]^{-2}.$$
Now evaluate each factor step by step.
The second factor is a square, so
$$\bigl[ML^{2}T^{-1}\bigr]^{2} = [M^{2}L^{4}T^{-2}].$$
The third factor is simply
$$\bigl[M\bigr]^{-5} = [M^{-5}].$$
The fourth factor has a power $$-2$$, therefore
$$\bigl[M^{-1}L^{3}T^{-2}\bigr]^{-2} = [M^{2}L^{-6}T^{4}].$$
Collecting all four results we have
$$[P] = [ML^{2}T^{-2}]\,[M^{2}L^{4}T^{-2}]\,[M^{-5}]\,[M^{2}L^{-6}T^{4}].$$
Now combine the exponents of each fundamental dimension $$M$$, $$L$$ and $$T$$ separately.
Mass $$(M)$$:
Exponent $$1 + 2 - 5 + 2 = 0$$
Length $$(L)$$:
Exponent $$2 + 4 + 0 - 6 = 0$$
Time $$(T)$$:
Exponent $$-2 - 2 + 0 + 4 = 0$$
Hence the net dimensional formula is
$$[P]=[M^{0}L^{0}T^{0}].$$
This shows that $$P$$ is dimensionless.
Looking at the given options, this matches Option D.
Hence, the correct answer is Option D.
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