not to mention the number and the weight of the projectiles Accelerator is throwing at him.
When IB contacts with Railgun, its primary effect is negated.
Based on the formula from
this, If I = 0, then F = 0.
Sidenote: 空気摩擦でコインが溶けてしまうため射程は50ｍ程。 (atwiki.jp)
It seems the coin will melt after a distance.