This is essentially just a matter of limits, without which the world wouldn't make any sense. So you must explain that if you move your hand closer to an objec

This is essentially just a matter of limits, without which the world wouldn't make any sense. So you must explain that if you move your hand closer to an object, technically you are halving the distance infinitely many times, but if 0.999... != 1 then your hand would never touch anything.