Assignment:
A charge of 1 µC is distributed uniformly along the circumference of a circle with a radius of 30 cm. How much external energy is required to bring a charge of 61 µC from infinity to the center of the circle? Let ke = 8.98 x 109 nm2/C2. Answer in units of J.
Provide complete and step by step solution for the question and show calculations and use formulas.