system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a terminal velocity for a buoyant object rising through liquid water?

If so, how would one calculate it?
gpt
The forces involved are weight (W), buoyancy (B), and drag (D).

Applying Newton’s second law, we find that W + D = B, or D = B - W.

The buoyant force is ρ*_f_*gV, where ρ*_f_* is the density of the fluid. The weight is ρgV, where ρ is the density of the object. And the drag is some function of the velocity; we can assume linear drag for low Reynolds number flows, so D = bv.

So the terminal velocity is calculated at steady state, when these forces are all balanced, and the result is v*_t_* = (ρ*_f_* - ρ)gV/b.

So it increases with the density difference, and decreases with the linear drag coefficient of the object.