1. The problem statement, all variables and given/known data What is the escape speed of an electron launched from the surface of a 1.0-cm-diameter glass sphere that has been charged to 10nC? 2. Relevant equations Given: d= 1.0cm r= 0.05cm= 0.0005m q1 = 10nC = 10 x 10-9 (sphere) q2 = -1.6 x 10-19 (electron) Equation: U = (kq1q2)/r KE= ½mv2 3. The attempt at a solution So, if the sum of kinetic and potential energy is supposed to be zero, then I get: KE + U = 0 ½me(ve)2 + (kq1q2)/r = 0 ½(9.11 x 10-31)(v)2 + ( (8.99 x 109) (10 x 10-9) (-1.6 x 10-19) ) / (0.0005) = 0 If I solve the above equation^^, I get ve= 2.5 x 108 m/s, which is incorrect. The correct answer is 8.0 x 107 m/s. I am not sure what I am doing incorrectly, any help is appreciated. Sorry about the mess, I can't seem to figure out how to use TeX!