Problem: An insulating sphere of radius 0.160m has uniform charge density 8.30 × 109 C/m3. A small object that can be treated as a point charge is released from rest just outside the surface of the sphere. The small object has positive charge 3.80 × 106 C.
Part A: How much work does the electric field of the sphere do on the object as the object moves to a point very far from the sphere?
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I need help to find how much work does the electric field of the sphere do on the object.