The electric potential at the centre of two concentric half rings of radii $R_1$ and $R_2$, having same linear charge density $\lambda$ is
  • A$\frac{2 \lambda}{\in_0}$
  • B$\frac{\lambda}{2 \in_0}$
  • C$\frac{\lambda}{4 \in_0}$
  • D$\frac{\lambda}{\in_0}$
JEE MAIN 2023, Diffcult
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