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It is commonly said that the electric force is much stronger than the gravitational force. Indeed, Coulomb's constant $k_e$ is much larger than the gravitational constant $G$ but they are measured in different units so it is not a reasonable comparison. With other units, it could be reversed.
Consider two electrons in space far from any matter. There will be a tiny gravitational attractive and a much larger electric repulsion.
Consider two protons. The electric repulsion will be the same. The gravitational attraction will be much larger (than for the electrons) but still much smaller than the electric repulsion.
So, those observations support that the electric force is stronger.
However, now consider two neutrons. The gravitational attraction is slightly greater than for the protons. There is no electric repulsion or attraction.
Is there some absolute sense in which the electric force is stronger?