Minor Alchemy allows you to transmute one object into a different material. What happens if the object is in motion (example: arrow in flight) when it reverts? What is the effect of mass changing while in motion? Does it stay at the same speed, and somehow the reverting just gives it a huge increase in momentum? Does it slow down, conserving the amount of momentum? If the rules specify (doubtful) then great. If not, I'd like some sort of a physics perspective on the question.
I'm mostly worried about two things:
- If it doesn't change speed, you could just throw a very heavy object that has been transmuted to be really light, then release the transmutation right at the end, landing with a hugely powerful amount of force?
- If it does change speed based on mass and momentum, then you could shoot a ballista with a spear of a very light metal transmuted into a very heavy one, then reverted once it was airborn, giving it a huge speed boost. No way you would normally be able to send that light of a spear with that much force.
Either way, either you get an advantage from going from light to heavy, or you get an advantage in going from heavy to light.