A very small charge q0 is placed at a point r in space. This region contains a number of other charges fixed in space. You measure the force on charge q0 ( Fonq0 ), and use this force to conclude that the electric field at r is E = Fonq0 /q0. If q0 is replaced by q1 = q0/4 and the process is repeated, then Fonq1 would be closest to ______

Consider an electron followed by a proton lying in a horizontal line and separated by 500 nm. Draw a picture that shows how the field lines would appear for the pair separated by this distance