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Question
A square metal plate of area 100 cm2 moves parallel to another plate with a velocity of 10 cm/s, both plates immersed in water. If the viscous force is 200 dyne and the viscosity of water is 0.01 poise, what is the distance between them?
Solution
F = `η"A""dv"/"dx"`
∴ dx = `η"A""dv"/"F" = 0.01 xx 100 xx 10/200 = 0.05` cm
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