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Question
QUESTION: hello, THIS IS NOT A HOMEWORK QUESTION I AM 38YO!
please tell me how i can work out how many farads would be stored in a sphere of 75cm?
also how big a sphere would be to store a 0.1 microfarad.
THANK YOU,
Gene

That's pretty much all you need, that formula, for both of those.

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QUESTION: please tell me, in the formula given in the article how do i do that sum on the calculator in windows7. i do not see the Eo button. please could you write it out so i can follow the template. also there is the google calculator that might be suitable. but i do not know how to punch it in. also how do i put in the air & surface quantities (or are they insignificant).
thank you,
Gene

ANSWER: It's not a button on a calculator, it's a physical constant for empty space (nearly identical to air).  From earlier in the article, "ε0 is the electric constant (ε0 ≈ 8.854×10−12 F m–1)."  R is obviously the radius. There's no sum, you just multiply the terms.

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QUESTION: thank you,
so i do:
4 x π x ε0 x R =
R is in cm?
but how do i put the ε0 into the equation?
thank you,
gene

I just gave you the number, 8.854×10−12 F/m.  The radius R is obviously in meters so that it cancels with the m in F/m to leave you with Farads (F).  Why did you put n in the equation instead of pi?  Nevermind, just multiply those four numbers.  Windows has a calculator built in.

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