An electron is released from rest at a distance of 0.500m from a large insulating sheet of charge that has uniform surface charge density 3.70×10-12C/m2 .
A) How much work is done on the electron by the electric field of the sheet as the electron moves from its initial position to a point 4.00×10-2m from the sheet?
B) What is the speed of the electron when it is 4.00×10-2m from the sheet?