I'm trying to find some sort of equation or any way to figure this out.. I want to be able to find the upward acceleration speed of any certain amount/density/temperature of air rising under water of any certain amount/density/temperature.

Please help! I know about buoyancy and how to calculate the amount of the upward force, that the upward force is determined by the amount of water that is being displaced.. but i dont know how to determine how fast that amount of air will rise!

Help help Help!