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fball558
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Earths potential?
the problem reads as folloed
Energy prospectors from a distant planet are inspecting the Earth to decide if its electrical energy resources are worth stealing. Measurements reveal that Earth's electric field extends upward for 800 m and has an average magnitude of 190 V/m. Estimate the electrical energy stored in the atmosphere.
our TA gave us a hint and said
You may treat the atmosphere as a flat slab with an area equal to the surface area of the earth.
i tried to derive an equation. i keep getting the wrong answer so please check my math and see if I am doing it wrong or just some calculation error.
i started with
U=1/2 Eo * E^2 Eo is 8.85e^-12
then i went to
U=EV substitued V=4/3pir^3 so got
U=E4/3pi*r^3
this is where i got stuck. i asked my TA and he said i was doing good so far.
i played around with some stuff and got my U (potential) as follows
U=E4pi*r^2*d
but i get the wrong answer. any help would be great ;)
thanks
Homework Statement
the problem reads as folloed
Energy prospectors from a distant planet are inspecting the Earth to decide if its electrical energy resources are worth stealing. Measurements reveal that Earth's electric field extends upward for 800 m and has an average magnitude of 190 V/m. Estimate the electrical energy stored in the atmosphere.
our TA gave us a hint and said
You may treat the atmosphere as a flat slab with an area equal to the surface area of the earth.
The Attempt at a Solution
i tried to derive an equation. i keep getting the wrong answer so please check my math and see if I am doing it wrong or just some calculation error.
i started with
U=1/2 Eo * E^2 Eo is 8.85e^-12
then i went to
U=EV substitued V=4/3pir^3 so got
U=E4/3pi*r^3
this is where i got stuck. i asked my TA and he said i was doing good so far.
i played around with some stuff and got my U (potential) as follows
U=E4pi*r^2*d
but i get the wrong answer. any help would be great ;)
thanks
