The atom is now like a tiny bar positively charged at one end and negatively charged at the other. Because of Coulomb's Law, the attraction to the ion of the nearer oppositely charged end is greater than the repulsion of the farther similarly charged end and the atom as a whole is drawn to the ion. You are increasing the electric potential energy of the object that carries the charge by 10 joules. With no friction, the 10 joules of potential energy will turn to 10 joules of kinetic energy at the starting point when the charge is released. Assuming the body of the car is metal and not fiberglass, the charge buildup that attracts a lightning strike will spread itself evenly over the metal so that the interior electric field is zero.
Nothing inside is charged, hence nothing attracts the lightning.
If lightning does strike the car, the charge flow to ground will take the path of least resistance through the metal rather than through the top of your head, and down the wet outer surface of the rubber tires. This solution involves only a relative distance, so the values of the charges don't matter. From Coulomb's Law, the force is . The value of the square of the charge is . Taking the square root gives .