# Feel like sleeping?

Long cylinder of radius $$R$$ is displaced along its axis with a constant velocity $$v$$ inside a stationary cylinder of radius $$r$$. The space between the cylinders is filled with viscous liquid .Find the velocity of liquid as a function of the distance $$x$$ from the axis of cylinders. Flow of liquid is assumed to be laminar. $$V= vln[ax/r]/ln[bR/r]$$. Find $$(a+b)^2$$.

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