Correct way to calculate energy in Bohr Atom Model

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The discussion focuses on the correct calculation of energy in the Bohr Atom Model, specifically addressing the integration of Coulomb's force and its implications for potential energy. The user encountered a discrepancy when integrating the attractive Coulomb force, leading to a positive energy result that contradicts expected outcomes. The confusion arises from the treatment of charges and the definition of potential energy, particularly the sign conventions used in the equations. The correct approach involves using the full charge values in the potential energy calculation, ensuring that the negative sign from the attractive force is appropriately accounted for.

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Bassalisk
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I was deriving Bohr model formulas and I stumbled upon a problem.

When I use the postulate that says that you can apply Newtonian Mechanics to orbiting electron, I wrote the Coulomb's force as following:


Fc=(-e)*Z*e/(4pi(epsilon0)*r^2)


Minus from the electron means that the force will be attractive. But when I integrated it to get the energy I got a minus from integration. Now if I put in the charges in, I got that minus like from coulombs force and those 2 cancel out, leaving me with positive energy.


I escaped from this by using potential energy as positive and substituting charges like I did in Coulomb's Force, but this is workaround and its not mathematically correct.

I attached a relevant image.

What is full correct way to do this?
 

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Since the F = -dV/dr, that would make dV = -F dr. I think you used a plus.
 
Thats by definition? So, I put full charge values into energy too, not by absolute value?
 
E_potential = - int Fc dr

please check the definition of potential energy
 
Again, I do enter charges by normal value, not absolute value, that would get rid of minus from the electric charge of electron (-e)?
 

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