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Question 1.8: Determine the viscosity of lubricant between two flat plates......

Determine the viscosity of lubricant between two flat plates, one fixed and other moving with velocity 0.60 m/s under a force of 5 N/m². The plates are 0.5 mm apart.

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Given,

Velocity, V = 0.6 m/s

Force, F = 5 N/m²

\text { Thickness of fluid film }=0.5  mm =0.5 \times 10^{-3}

Assuming linear velocity distribution,

\begin{aligned} \tau & =\mu \frac{d u}{d t} \\ 5 & =\mu \frac{0.6}{0.5 \times 10^{-3}} \\ \mu & =4.1667 \times 10^{-3}  Pa  s \end{aligned}

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