MCQ
The charge per unit length of the four quadrant of the ring is $2\ \lambda , - 2\ \lambda , \lambda$ and $- \lambda$ respectively. The electric field at the centre is
- ✓$-$ $\frac{\lambda }{{2\pi {\varepsilon _0}R}}\,\hat i$
- B$\frac{\lambda }{{2\pi {\varepsilon _0}R}}\,\hat j$
- C$\frac{{\sqrt 2 \,\,\lambda }}{{4\pi {\varepsilon _0}R}}\,\hat i$
- DNone
