Question: an electron with a speed of 750 108 cms...

An electron with a speed of 7.50 ✕ 10⁸ cm/s enters an electric field of magnitude 1.00 ✕ 10³ N/C, traveling along the field in the direction that retards its motion.

(a) How far will the electron travel in the field before stopping momentarily and
m
(b) how much time will have elapsed?
s

(c) If, instead, the region of electric field is only 7.00 mm wide (too small for the electron to stop), what percentage of the electron's initial kinetic energy will be lost in that region?
%