A horizontal beam of electrons initially moving at $4.0 \times 10^{7} \mathrm{m} / \mathrm{s}$ is deflected vertically by the vertical electric field between oppositely charged parallel plates. The magnitude of the field is $2.00 \times 10^{4} \mathrm{N} / \mathrm{C} .$ (a) What is the direction of the field between the plates? (b) What is the charge per unit area on the plates? (c) What is the vertical deflection $d$ of the electrons as they leave the plates?
FIGURE CANT COPY