1. The problem statement, all variables and given/known data As an electron moved through a region of space, its speed changed from an initial velocity of vi=8114.3 km/s to the final velocity vf=2233.7 km/s. The electric force was the only force acting on the electron. Across what potential difference did the electron travel? 2. Relevant equations Qe * V = (0.5 * m * Vf^2) - (0.5 * m * Vi^2) Qe = Charge of Electron = -1.602 * 10^(-19) V = Potential Difference m = Mass of Electron 3. The attempt at a solution V = [( 0.5 ) * ( 9.11*10^-31 kg ) * ( 2.2337*10^6 m/s )^2] - [( 0.5 ) * ( 9.11*10^-31 kg ) * ( 8.1143*10^6 m/s )^2] / ( -1.602*10^-19 C ) The answer I keep getting is V = 173 Volts, but that's incorrect. It may be my math, but if anyone can help I would appreciate it.