Will a sphere with 100C charge weigh more than one with 0.0000001C?

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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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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?
 
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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
 
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Bob, I think it's best for the OP to tell us what he is trying to calculate rather than guessing.