Hey, I recenty took an exam and the professor asked us to turn in a corrected version of the exam based on the comments he made to us (I guess people didn't do as well as he expected). On one of the problems it asks:(adsbygoogle = window.adsbygoogle || []).push({});

How much work does it take for you to move a charge Q from infinity to the center of the sphere (all charge is located at the surface)?

I already calculated the potential from infinity to the surface of the sphere as well as the work required to create the sphere. When I originally did the problem, I did this:

W=(1/2)*Q*(Work to create sphere)

He made a comment circling that and then: Q*delta-V(due to q=4 pi R^2) from infinity to R (R=surface of sphere).

I don't really know what the professor means by that and I can't really ask him right now either. Does anyone have an idea what that comment is supposed to mean or how I should be correcting this problem?

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# Homework Help: Work needed to move charge from infinity to center of sphere

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