A proton is fired directly into a uniform electric field that is able to bring the charge momen- tarily to rest.
(a) What must be the orientation of the electric field relative to the velocity of the proton?
(b) What type of charge configuration would generate a uniform electric field?
(c) If the proton is initially traveling at 5% the speed of light, what field strength will stop the charge within 1.00 cm of entering the field region?
(d) How much work does the electric field do in stopping the proton?