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A thin horizontal disc of radius R=10cm ...


A thin horizontal disc of radius R=10cm is located with in a cylindrical cavity filled with oil whose viscosity `eta=0.08`P (figure) The distance between the disc and the horizontal planes of the cavity is equal to `h=1.0` mm find the power developed by the viscous forces acting ont he disc when it rotates with the angular velocity `omega=60rad//s`. The end effect are to be neglected.

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