Problem 2.61[Difficulty: 3]Given:Data on the viscometerFind:Time for viscometer to lose 99% of speedSolution:The given data isR50mm⋅=H80mm⋅=a0.20 mm⋅=I0.0273 kg⋅m2⋅=μ0.1Ns⋅m2⋅=The equation of motion for the slowing viscometer isIα⋅Torque=τ−A⋅R⋅=where αis the angular acceleration and τis the viscous stress, and A is the surface area of the viscometerThe stress is given byτμdudy⋅=μV0−a⋅=μV⋅a=μR⋅ω⋅a=where Vand ωare the instantaneous linear and angular velocities.HenceIα⋅Idωdt⋅=μR⋅ω⋅a−A⋅R⋅=μR2⋅A⋅aω⋅=Separating variablesdωωμR2⋅A⋅aI⋅−dt⋅=Integrating and using IC
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This note was uploaded on 10/19/2011 for the course EGN 3353C taught by Professor Lear during the Fall '07 term at University of Florida.