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# PHYSICS SPECIFIC CHARGE HELP please Watch

1. Which of the two isotopes of uranium (U 92, 235) or (U 92, 238) , has the largest specific charge?

Does anyone know how to explain why uranium 235 has a larger specific charge than 238???? I know the charge to mass ratio but I don't understand it!!!!

Thanks.
2. (Original post by CorpusLuteum)
Which of the two isotopes of uranium (U 92, 235) or (U 92, 238) , has the largest specific charge?

Does anyone know how to explain why uranium 235 has a larger specific charge than 238???? I know the charge to mass ratio but I don't understand it!!!!

Thanks.
The protons are the charged particles in the nucleus. Both isotopes of Uranium have the same number of protons, because atoms of the same elements have the same number of protons by definition. Thus both isotopes have the same charge.

But U-238 has more mass than U-235, so U-235 has a larger charge to mass ratio: x/235, instead of the smaller x/238. Hence U-235 has a greater specific charge.
3. (Original post by K-Man_PhysCheM)
The protons are the charged particles in the nucleus. Both isotopes of Uranium have the same number of protons, because atoms of the same elements have the same number of protons by definition. Thus both isotopes have the same charge.

But U-238 has more mass than U-235, so U-235 has a larger charge to mass ratio: x/235, instead of the smaller x/238. Hence U-235 has a greater specific charge.
Ahhhhh, thanksssssSO MUCH!!!!

Could you help me out with this question:

Show that the specific charge of a nucleus of the isotope U 92, 238 is approximately 0.4 times the specific charge of a proton?
4. (Original post by K-Man_PhysCheM)
The protons are the charged particles in the nucleus. Both isotopes of Uranium have the same number of protons, because atoms of the same elements have the same number of protons by definition. Thus both isotopes have the same charge.

But U-238 has more mass than U-235, so U-235 has a larger charge to mass ratio: x/235, instead of the smaller x/238. Hence U-235 has a greater specific charge.
Also, I don't understand why a proton has a smaller specific charge than an electron.???
5. (Original post by CorpusLuteum)
Also, I don't understand why a proton has a smaller specific charge than an electron.???
An electron has roughly 1/1837th the mass of a proton. The charge of an electron is -1.6x10^-19, and proton is 1.6x10^-19If you divide the same number by a smaller divisor you get a bigger number than if you divide by a bigger divisor.

For example 10/5 < 10/2
6. (Original post by shipreck)
an electron has roughly 1/1837th the mass of a proton. The charge of an electron is -1.6x10^-19, and proton is 1.6x10^-19if you divide the same number by a smaller divisor you get a bigger number than if you divide by a bigger divisor.

For example 10/5 < 10/2
rigggghtt!!!! Thank youuuu

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