A van de Graaff generator puts negative charge on a metal sphere.(adsbygoogle = window.adsbygoogle || []).push({});

Suppose theradius of the sphere is a = 6.9 cm, and thecharge on the sphere is Q = -1.0×10-8 C.Determine the electric field strength at a point 1.0 cm from the surface of the sphere (outside the sphere).

I've done this problem over and over and am not getting the correct answer.

I've used E = F/q and made F = kq/r^2

...from there, I don't know what to do. Please help. Thanks

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# Homework Help: Van de Graff Problem

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