(Solved):   Q2) A plastic rod has been bent into a circle of radius \( R \). It has a charge \( Q_{1}= ...

 

Q2) A plastic rod has been bent into a circle of radius \( R \). It has a charge \( Q_{1}=3 q \) uniformly distributed along one quarter of its circumference and a charge \( Q_{2}=-2 q \) uniformly distributed along the rest of the circumference as shown in the Figure. The electric potential at point \( P \), on the central axis of the circle at distance \( D \) from its center is a) \( \mathrm{kq} / \mathrm{R} \) b) \( \mathrm{kq} / \mathrm{D} \) c) \( \mathrm{kq} /\left(\mathrm{R}^{2}+\mathrm{D}^{2}\right)^{1 / 2} \) d) \( (3 \mathrm{kq} / \mathrm{R})-(2 \mathrm{kq} / \mathrm{D}) \)