I have a object which travels down a chamber filled with fluid with perforated bottoms. As the objects travel with constant velocity it will de-accelerate due to resistance provided by displacing fluid. Density of fluid is known as well as force pushing object. I am neglecting the drag as OD of object is equal to ID of chamber so it will only force object out. will only calculating change in acceleration over time with inertial resistance ? Intent is to calculate impact of object when it hit bottom of chamber. Any advise on how to approach this issue.