Electric Potential of Uniformly Charged Sphere

ktbobabee@aol
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Homework Statement


A nonconductive sphere has radius R=2.31 cm and uniformly distributed charge q==3.5 fC. Take the electric potential at the sphere's center to be V=0. What is V at the radical distance r=1.45cm and at r=2.31 cm


Homework Equations


Gauss' Law
V=E*ds


The Attempt at a Solution


E=kqr/R^3
then V=E*ds
I keep getting an answer that is 20 times smaller then the actual.


 
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Your second equation "V=E*ds" is not correct. The RHS is a differential element, while the LHS is not. Besides, what is "s"?

Please show your work more explicitly. With what you've shown so far, there is no way one can tell you exactly where your error is.
 
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