OR An electron is projected from the right plate of set I directly towards its left plate. It just comes to rest at the plate. The speed with which it was projected is about: (Take $(e/m) = 1.76 \times 10^{11} \text{ C/kg}$) (A) $1.3 \times 10^5 \text{ m/s}$ (B) $2.6 \times 10^6 \text{ m/s}$ (C) $6.5 \times 10^5 \text{ m/s}$ (D) $5.2 \times 10^7 \text{ m/s}$