Figure shows a rod $$AB$$, which is bent in a 120° circular arc of radius $$R$$. A charge $$(-Q)$$ is uniformly distributed over rod AB. What is the electric field $$\vec{E}$$ at the centre of curvature O?

A

$$\frac{3\sqrt{3}Q}{8\pi^2 \varepsilon_0 R^2} \hat{i}$$

B

$$\frac{3\sqrt{3}Q}{8\pi \varepsilon_0 R^2} \hat{i}$$

C

$$\frac{-3\sqrt{3}Q}{8\pi^2 \varepsilon_0 R^2} \hat{i}$$

D

$$\frac{3\sqrt{3}Q}{16\pi^2 \varepsilon_0 R^2} \hat{i}$$