For this question, I have solved letters a, b and c. I'm stuck at letter d. 1. The problem statement, all variables and given/known data Two point charges ql = +2.40 nC and q2 = -6.50 nC are 0.100 m apart. Point A is midway between them; point B is 0.050 m from ql and 0.060 m from q2 (Fig). Take the electric potential to be zero at infinity. Find (a) The potential at point A; (b) The potential at point B; (c) The work done by the electric field on a charge of 2.50 nC that travels from point B to point A. (d) The speed of the 2.50 nC when it reaches point A, if it starts from rest at point B 2. Relevant equations KE = 1/2 m v2 ? 3. The attempt at a solution I have solved a, b and c a) VA = -737 V b) VB = -704 V c) WB->A = +8.2 x 10-8 J Now I'm stuck at letter D, how do i find the speed? I assume that I might need the equation of KE = 1/2 m v2.. But I dont know how to do it. What I did was to put +8.2 x 10-8 J as my KE. However, I do not have a mass, so how do I do this?