1. The problem statement, all variables and given/known data A proton moving to the right along the x-axis at 3.8*10^5m/s, enters a region where the electric field of intensity 5.6*10^4n/c points to the left. How far will the proton move before its speed reaches zero? Describe the subsequent motion in deatail/ 2. Relevant equations dont know whethere to about doing this with force of energy so I really dont know. 3. The attempt at a solution Im not really sure how to start this, some helpful hints would be appretiated. Thanks.