I'm bad at physics

What happens to the force between the charges if the distance between the charges is increased to two times its original value? Value of the force is increased by two. Value of the force is decreased by two. Value of the force is decreased by four. Value...

A metal sphere has a charge of -6 µC. How many excess electrons are there on the sphere? 4x10^-13 10x10^13 4x10^13 10x10^-13 I'm stuck between A or D...

What equation illustrates the relationship between the electric field strength and the potential difference? E = d / v E = v / d d = E(v) E = v(d) I'm honestly clueless on this one