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A block 0.1 m square, with 5 kg mass, slides down a smooth incline, 30° below the horizontal, on a film of SAE 30 oil at 20°C that is 0.20 mm thick. If the block is released from rest at t = 0, what is its initial acceleration? Derive an expression for the speed of the block as a function of time. Plot the curve for V(t). Find the speed after 0.1 s. If we want the mass to instead reach a speed of 0:3 m/s at this time, find the viscosity μ of the oil we would have to use.
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Fox and McDonald's Introduction to Fluid Mechanics
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