Which sphere will be heavier: one with a charge of 0.0000001C or one with 100C?

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Discussion Overview

The discussion centers around the question of whether two spheres with different charges (0.0000001C and 100C) will differ in weight, given that they have the same physical properties. Participants explore the relationship between charge and mass, as well as the implications of electron mass and charge removal.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant expresses confusion about the weight comparison of two charged spheres, questioning which would be heavier.
  • Another participant asserts that charge does not contribute to mass or weight.
  • A participant provides a calculation suggesting that a sphere with +100C of charge would have a lesser mass than an identical sphere with -100C, based on the mass of electrons.
  • Further clarification is requested regarding the calculation of mass associated with 100C of electrons, including the relationship between charge and the number of electrons.
  • Another participant emphasizes the need for clarity on what is being calculated, questioning whether it pertains to the mass of electrons or the potential energy associated with the charge configuration.
  • A participant mentions that when considering the spheres in isolation, the negatively charged sphere would have more mass due to the presence of additional electrons.
  • One participant suggests that the original poster should clarify their intent rather than making assumptions about the calculations.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between charge and mass, with some asserting that charge does not affect weight while others propose calculations that suggest otherwise. The discussion remains unresolved, with multiple competing perspectives present.

Contextual Notes

There are unresolved assumptions regarding the definitions of mass and weight in the context of charged spheres, as well as the implications of electron removal on mass calculations.

astro2cosmos
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it may bit a fuzzy problem but still i have this confusion i.e suppose i have two sphere of same radius & all physical & material properties are same but 1st sphere has a charge of 0.0000001C & another have 100C. and if i measure the weight of both then which will be heavier?
 
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No, charge has no mass or weight.
 
hello Astro-
One gram molecular weight (GMW) of electrons has a mass of 0.0005446 grams. 100 C of electrons has a mass about 96 times less. So a sphere with +100 C of charge will have a lesser mass than an "identical" sphere with -100C, because electrons have a negative charge.

"identical" means the same number of protons and neutrons.
Bob S
 
Bob S said:
hello Astro-
One gram molecular weight (GMW) of electrons has a mass of 0.0005446 grams. 100 C of electrons has a mass about 96 times less. So a sphere with +100 C of charge will have a lesser mass than an "identical" sphere with -100C, because electrons have a negative charge.

"identical" means the same number of protons and neutrons.
Bob S

hey bob!
can u please explain that how 100 C of electrons has a mass about 96 times less.
 
astro2cosmos said:
hey bob!
can u please explain that how 100 C of electrons has a mass about 96 times less.
Sure. A GMW (gram molecular weight) of protons has a mass of 1 gram, and contains 6,02 x 1023 protons (approximately). The mass of an electron has a mass 1836 times less (remember hydrogen atom). The charge on an electron is 1.6 x 10-19 Coulomb, so a Coulomb contains 6.25 x 1018 electrons. So a GMW of electrons contains 96,320 Coulombs of electrons.
Bob S
 
I think you'll need to supply more information about what exactly you're trying to calculate here. Is it the mass of electrons? (And remember, if I have a positive charge, I'm removing electrons). Is it the relativistic mass equivalent of the potential energy from assembling this charge configuration? Is it something else?
 
[STRIKE][/STRIKE]
Vanadium 50 said:
I think you'll need to supply more information about what exactly you're trying to calculate here. Is it the mass of electrons? (And remember, if I have a positive charge, I'm removing electrons). Is it the relativistic mass equivalent of the potential energy from assembling this charge configuration? Is it something else?
Hi Vanadium50-
This is calculating the rest mass of each sphere in isolation. [STRIKE][STRIKE][STRIKE]When the two spheres are brought close together, the Coulomb force is about [STRIKE]8[/STRIKE]9 billion (9 x 109) Newtons at 100 meters, so perhaps a kilometer might be better[/STRIKE][/STRIKE][/STRIKE].
[STRIKE]Because the positive sphere is missing 100 Coulombs of electrons, and the negative one has 100 Coulombs of extra electrons,[/STRIKE] the more negatively charged sphere has more mass.
Bob S
 
Last edited:
Bob, I think it's best for the OP to tell us what he is trying to calculate rather than guessing.
 

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