How would a non-lethal, hand-held ‘firearm’ (as in not a melee weapon) produce enough ‘force’ (I’m using this word lightly, not as a physicist) to throw an attacker back a minimum of ten feet, work?
Right now my understanding is that this would be impossible given our current knowledge of science / physics, but I’d like this firearm, in my fictional world, to not entirely be pulled from thin air.
This firearm does not need to be long-ranged (my original, non-informed concept was akin to a shotgun that shoots only highly compressed air strong enough to throw someone back without firing an actual projectile).
I have considered shockwave technology, like the “Thunder Cannon,” but none small / portable enough exist and even if they did, one strong enough to throw an adult human backward would also liquidity their insides and the recoil would likely kill the one shooting.
I’m asking for ideas, not breakthroughs: feel free to create any scenarios that allow your’s to work.