An object moving in a liquid experiences a linear drag force: D⃗ =(bv, direction opposite the motion), where b is a constant called the drag coefficient. For a sphere of radius R, the drag constant can be computed as b=6πηR, where η is the viscosity of the liquid.
Drag equation is given in the problem.
The Attempt at a Solution
I am working toward a solution but there is something that troubles me. Drag, D = bv, depends on velocity. But, velocity changes continually from the point the marble first begins to slow down, until it reaches zero. So how can I come up with net force for this to solve the kinnematic equations, when they are dependant on a constantly changing velocity?