Hello everyone, I managed to get Parts (a) and (b) of this problem but can't get the last for some reason. A metal sphere of radius 15cm has a net charge of 2.0E-8C. THe question is, at what distance from the sphere's surface has the electric potential decrased by 700V? Well i found the electric field to be 7992.7 N/C at the sphere's surface. I also found If V = 0 at infinity, what is the electric potenital at the sphere's surface? I used Vsurface = kQ/(r). to find Vsurface being equal to 1198.9V. But I can't figure this part out. I pluged in 700V for Vsurface and solved for r, and got .2569m. r = kQ/Vsurface; This was wrong So i tried, [tex]Vf - Vi = -\int E.ds [/tex] Plugged 700V for Vf-Vi and solved for ds, because i know E from above and I know Vf-Vi, and i got .584m, also wrong any ideas? thanks(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: At what distance has spheres decreased Electric potential by 700V?

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