A small positively charged sphere of charge is fixed in space
PHYSICS · Multi-part · CBSE · Physics · Electrostatic Potential and Capacitance · Electrostatic Potential and Capacitance
Problem
A small positively charged sphere of charge +6.0μC is fixed in space. A second identical sphere, initially very far away, is slowly brought straight in toward the first until the center–to–center separation is 0.12m. Throughout the motion the speed is negligibly small so that kinetic energy changes can be ignored.
(a) Describe whether the external agent must do positive work, negative work, or zero work on the moving sphere during the approach. Justify your answer without performing a numerical calculation.
(b) Explain how the electric potential energy of the two–sphere system changes during this process and relate your explanation to the work identified in part (a).
(c) If the external agent suddenly releases the second sphere when it reaches the 0.12m separation, qualitatively describe the subsequent energy transformations that occur in the system. Identify the forms of energy involved and how their magnitudes change.