My friend and I had a little discussion about added mass forces.
I always interpreted $F=ma$ as a cause-effect relationship, so I find rather uneasy to accept that the cause can instantaneously depend on the effect.
Is it fine to have a force which depends on an acceleration, in classical mechanics?
I came up with some possible solutions to this:
- It's perfectly fine for F=m a to be an implicit equation with respect to a.
- The time derivative of the velocity appears as the result of an approximation of a time-delay.
- It arises due to assumptions made on the nature of the fluid (i.e. incompressible).
- None of them