1. The problem statement, all variables and given/known data I have a block of mass m on a horizontal surface, which is covered in oil. The tell me the viscous resistance force is a function of the velocity, F(v)=-cv1/2, where I am assuming c is a constant of some kind. I need to find the time that it will take for the block to stop. The initial velocity is V0 at x=0 2. Relevant equations Equations of motion Newton's laws 3. The attempt at a solution I thought that I could use ΣF=ma. Then in my equations of motion solve for a=(V-V0)/t Since the vertical forces cancel out, the equation would then be: -cv1/2=m((V-V0)/t) The problem is if I want the block to stop then V will be 0 and my equation doesn't work. Since the resistance is a function of V will I have to integrate it ?