Fel & Fg Interaction: Electron Count for Balance

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Discussion Overview

The discussion revolves around the interaction between electrostatic force (Fel) and gravitational force (Fg) in hypothetical objects composed of protons and electrons. Participants explore the conditions under which the repulsive electrostatic force can be less than the attractive gravitational force, considering different configurations of charged particles.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant calculated Fel and Fg between two protons at a distance of 1 mm, noting that these values change with the number of protons and distance.
  • Another participant pointed out that replacing protons with electrons reduces both Fel and Fg, suggesting a potential issue in balancing these forces.
  • A further contribution emphasized that atoms and molecules are primarily held together by electromagnetic and nuclear forces, rather than gravity, which is considered negligible in this context.
  • One participant proposed writing expressions for gravitational and electrostatic forces based on the number of protons (nP) and electrons (nE) to explore the relationship between these forces, noting the challenge of having one equation with two unknowns.

Areas of Agreement / Disagreement

Participants express differing views on the significance of gravitational force in the context of atomic structure, with some emphasizing its negligible role compared to electromagnetic and nuclear forces. The discussion remains unresolved regarding the balance of forces in hypothetical charged objects.

Contextual Notes

Limitations include the assumptions made about uniform distribution of charges and the simplification of complex atomic interactions. The mathematical expressions proposed are not fully resolved, leaving open questions about the relationship between nE and nP.

Praestrigiator
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I did the math and figured that Fel between two protons at 1 mm is 2.307E-22 N, and the Fg at the same distance is 1.867E-36 obviously these values change with the number of protons, and distance. this is an issue because I'm trying to imagine a hypothetical object as charged as possible while still held together by gravity. Assuming uniform distribution of protons and electrons, how many electrons are needed to make The repulsive force of Fel less than the attractive force of gravity on an object primarily comprised of protons? What about an object comprised of electrons?
 
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The biggest problem i see is that in replacing protons with electrons reduces both repulsive Fel and attractive Fg
 
Praestrigiator said:
The biggest problem i see is that in replacing protons with electrons reduces both repulsive Fel and attractive Fg

Atoms and molecules aren't held together by gravity. The force exists, of course, but is negligible compared to the other forces present. They are held together by the electromagnetic force at one level, and the nuclear force (extremely important) at another. Gravity is too weak to be considered here, don't you think? Protons are held together in nuclei not because "surrounding electrons reduce the repulsion between them causing gravity to become more prominent", but because of the strong nuclear force which binds the nucleons together. It is much stronger than the repulsive force between protons.
 
Last edited:
Praestrigiator said:
I did the math and figured that Fel between two protons at 1 mm is 2.307E-22 N, and the Fg at the same distance is 1.867E-36 obviously these values change with the number of protons, and distance. this is an issue because I'm trying to imagine a hypothetical object as charged as possible while still held together by gravity. Assuming uniform distribution of protons and electrons, how many electrons are needed to make The repulsive force of Fel less than the attractive force of gravity on an object primarily comprised of protons?
Let nP be the number of protons and nE be the number of electrons. Write down an expression for the gravitational force from nP+nE, and an expression for the electrostatic force. Set them equal.

You now have one equation in two unknowns, so you cannot solve. But you can solve for nE/nP
 

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