What Happens if Earth Had a Net Surface Charge Density?

AI Thread Summary
If Earth had a net surface charge density of 1.0 electron per square meter, the total charge on its surface would be approximately -82 microC. The electric potential just outside the Earth's surface would be around -0.12V, while the electric field would measure about 18 nV/m. Participants in the discussion noted that calculating these values involved using the charge of an electron and applying electrostatic equations. One user initially struggled but found the calculations straightforward after clarifying the surface area of the Earth. The discussion highlighted the simplicity of the electrostatic principles involved.
gwenle1
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1. If the Earth had a net surface charge density of 1.0 electron per square meter a) what would be the total charge on the Earth's surface? b) what would be the electric potential and c) what would be the electric field, just outside the Earth's surface?






Attempt: I tried using charge of electron (-1.6 x 10^-19C/m^2) and rearranging equations of electrostatics but cannot come up with the answer.


The solutions should be -82microC, -0.12V and 18nV/m
 
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gwenle1 said:
1. If the Earth had a net surface charge density of 1.0 electron per square meter a) what would be the total charge on the Earth's surface? b) what would be the electric potential and c) what would be the electric field, just outside the Earth's surface?






Attempt: I tried using charge of electron (-1.6 x 10^-19C/m^2) and rearranging equations of electrostatics but cannot come up with the answer.


The solutions should be -82microC, -0.12V and 18nV/m
Welcome to PF!
It would be nice if we could see your attempt.
Start with a). The Earth has a surface charge density of 1 electron/m². How many m² does the Earth have? Thus, how many free electrons?
 


ok. Thanks for that clarification. I got part A of the question.
 


The rest came easily thereafter too.
Easier than I thought- simple plug in and solve!
 
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