I Calculating the Force of a Planet Using Energy and Radius

AI Thread Summary
Dividing a planet's energy (mc²) by its radius (R) yields a quantity with force units, but it does not represent an actual force and lacks relevance in physical terms. This calculation can relate to the ratio of the planet's radius to its Schwarzschild radius, indicating whether it could be a black hole; a ratio less than 1 suggests it is a black hole rather than a planet. The discussion emphasizes that arbitrary calculations can produce results with correct units but without meaningful physical significance. An analogy is drawn to illustrate that combining unrelated measurements can yield nonsensical results. The conversation concludes with an acknowledgment of understanding the explanation provided.
Sanev
I want to ask if we now the energy of a planet (mc2) and we divided that energy over the radius(R) of that planet what kind of force(F) we get --> mc2/Radius = F(?)
 
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That quantity has the same unit as a force, but it is not a force anywhere, and it has no relevance.

If you multiply it by a few fundamental constants you get the ratio of the object’s radius to its Schwarzschild radius (if it would be a black hole). If that ratio is smaller than 1 then you don’t have a planet, you have a black hole.
 
I'm sorry but i don't understand this IT HAS NO RELEVANCE. Why it doesn't have? Can you explain a little bit more. Thank you!
 
Multiply the width of your thumb by the number of days in a year and divide it by the duration of your last breakfast. The result has the units of a speed. Do you expect the result to have any relevance? Why not?
 
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I get it :D thank you for your answer :)
 
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