I need to calculate the force required to pull a copper ball radius 2.00cm upward through a fluid at the constant speed 9.00cm/s. The drag forse is to be proportional to the speed, with proportionality constant .950kg/s. Ignore any boyant force.(adsbygoogle = window.adsbygoogle || []).push({});

What I did so far was figure out the resistive force using the equation: R=-bv, where b= .950kg/s and v= .09m/s

So that gives me -.0855Newtons.

My equation set up so far is:

SumYForces = mg+ Resitive force= Pull Force

and then from there I have no clue, the answer in the back of the book is 3.01 N, but I just can't seem to get it. Thanks -anne

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# Homework Help: Resistive force

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