Final answer:
The question is about determining the characteristics of an electron's motion in a uniform electric field, such as its velocity, distance traveled, and time taken to come to rest, according to physics principles.
Step-by-step explanation:
An electron moving at a constant speed in a uniform electric field is being described from a physics perspective. For example, an electron has an initial velocity of 5.00 × 106 m/s in a uniform electric field strength of 2.00 × 105 N/C. This electric field accelerates the electron in the direction opposite to its initial velocity. We're asked to determine various characteristics about the electron's motion, such as the direction of the electric field, the distance the electron travels before coming to rest, and the time it takes to come to rest or reach a certain velocity, and other related factors depending on additional conditions of the scenario.