I downvoted for a number of reasons:
First, all of the edits, therefore all of the phrasing and word choices, belong to the original poster. And if the OP can ask the question in terms of joules, they can almost certainly plug in the \$m \times g \times h\$ formula that the single answer used. This may be presumptuous on my part, but it did not strike me as a question trying to solve an actual problem.
Second, the question is terribly posed. Why? Because the Strength stat is an abstraction, a dramatic simplification of a complex concept so that we can stop worrying about the fine details and get on with playing. In the real world, arm strength, leg strength, grasping strength, are all different things. In the game world, Attack bonuses, damage bonuses, lifting capacity, encumbrance are also different things. While they may be correlated, they are not unified, and there is no master conversion plan.
The only possible way this question can avoid being vague or opinion-based is to add enough specific details to point to a particular answer-- in this case, the \$m \times g \times h\$ formula-based answer, which is so specific that it even specifies the height of the character...! This dramatically increased my "not an actual problem" sense.
Third, the first words of the question body (of every revision) are "D&D is not a science based or physics based game" before barreling on and asking for a science- or physics-based answer to a gaming question. So it seems to me that the OP knew, or at least suspected from the start, that there would be pushback on the question. That does not automatically invalidate the question, and would not alone have triggered my downvote, but it sure didn't help anything.
Fourth, on the same day, the same poster asked another question (also immediately closed) which took this one as a springboard for something even more ill-posed-- trying to get a joules-based number for "1 dmg" (which I assume is meant to be 1 hp worth of damage.)
All together, this just sets off alarm bell after alarm bell for me:
- It's a question I'm certain the OP could have answered just based on the specificity of the question;
- yet it dramatically misunderstands the relation of the game rules to the real world;
- While acknowledging that it does exactly that;
- And got almost immediately used by the same poster to launch an even more problematic question.
This is not a salvageable question. Mainly because of the second point-- broad questions will be too vague to answer, while specific questions are somewhat misleading by relying on an improper reduction of a complex phenomenon (human "Strength") to only one of its many facets.
The downvotes and close votes were proper, in my opinion.