Consider a laminar flow in the $x$ -direction between two infinite parallel plates (Couette flow). The lower plate is stationary and the upper plate is moving with a velocity of $1 \mathrm{~cm} / \mathrm{s}$ in the $x$ -direction. The distance between the plates is $5 \mathrm{~mm}$ and the dynamic viscosity of the fluid is $0.01 \mathrm{~N}-\mathrm{s} / \mathrm{m}^{2} .$ If the shear stress on the lower plate is zero, the pressure gradient, $\frac{\partial p}{\partial x},$ (in $\mathrm{N} / \mathrm{m}^{2}$ per $m,$ round off to 1 decimal place ) is

Consider a laminar flow in the $x$ -direction between two infinite parallel plates (Couette flow). The lower plate is stationary and the upper plate is moving with a velocity of $1 \mathrm{~cm} / \mathrm{s}$ in the $x$ -direction. The distance between the plates is $5 \mathrm{~mm}$ and the dynamic viscosity of the fluid is $0.01 \mathrm{~N}-\mathrm{s} / \mathrm{m}^{2} .$ If the shear stress on the lower plate is zero, the pressure gradient, $\frac{\partial p}{\partial x},$ (in $\mathrm{N} / \mathrm{m}^{2}$ per $m,$ round off to 1 decimal place ) is

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