Electrical charge problem (need assurance on an answer)

AI Thread Summary
The discussion centers on calculating the maximum charge a green pea can hold before discharging due to an electric field of 3.0×10^6 N/C. The initial calculation used an incorrect radius, leading to an incorrect charge value of approximately 4.85 nC. After clarification, the correct diameter was identified as 0.405 cm, resulting in a revised calculation that yielded a charge of about 5.5 nC. Participants confirmed the importance of using the correct radius in such calculations. The final answer reflects the accurate application of the formula for electric fields and charge.
AyooNisto
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Homework Statement



Dry air will break down and generate a spark if the electric field exceeds about 3.0\times 10^6 N/C How much charge could be packed onto a green pea (diameter 0.81cm ) before the pea spontaneously discharges?

Homework Equations



E = kQ/r^2
Q = Er^2/ k <-------this is the equation to use I believe

The Attempt at a Solution


(3*106)(3.81*10-3)2/8.988*109

resulting in an answer of 4.845160214*10-9 = 5*10-9

does this look right to you guys?
 
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The radius is not 3.81*10-3 m. Check.

ehild
 
figured it out, the diameter is .405
so the answer would be
(3*106)(4.05*10-3)2/8.988*109 = 5.5 *10^-9
Thank you for your help
ehild said:
The radius is not 3.81*10-3 m. Check.

ehild
 

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