mass dependency on charge

[astro2cosmos]

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????

[HallsofIvy]

No, charge has no mass or weight.

[Bob S]

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

[astro2cosmos]

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 plz explain that how 100 C of electrons has a mass about 96 times less.

[Bob S]

hey bob!
can u plz 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

[Vanadium 50]

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?

[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?
Hi Vanadium50-
This is calculating the rest mass of each sphere in isolation. When the two spheres are brought close together, the Coulomb force is about 89 billion (9 x 109) Newtons at 100 meters, so perhaps a kilometer might be better.
Because the positive sphere is missing 100 Coulombs of electrons, and the negative one has 100 Coulombs of extra electrons, the more negatively charged sphere has more mass.
Bob S

[Vanadium 50]

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