g a uniform electric field has magnitude e and is directed in the negative x direction. the potential difference between point a (at x= 0.60 m) and point b (at x= 0.90 m) is 310 v. Part A Which point, a or b, is at the higher potential? Part B Calculate the value of E. Express your answer using two significant figures. Part C A negative point charge q = -0.200 mu C is moved from b to a. Calculate the work done on the point charge by the electric field. Express your answer using two significant figures.