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1-3 What is the no-slip condition? What cause it?
1-8 Define stress, normal stress, shear stress, and pressure.
2-18 A pump is used to transport water to a higher reservoir. If the water
temperature is 25℃, determine the lowest pressure that can exist in the pump
without cavitation.
2-65 Contrary to what you might expect, asolid steel ball can float on water
due to the surface tension effect. Determine the maximum diameter of a steel
ball that would float on water at 20℃. What would your answer be for an
aluminum ball? Take the density of steel and aluminum balls to be 7800 kg/m^3
and 2700 kg/m^3, respectively.
2-74 Some non-Newtonian fluids behave as a Bingam plastic for which shear
stress can be expressed as τ＝τy＋μ(du/dr). For Iaminar flow of a Bingham
plastic in a horizontal pipe of radius R, the velocity profile is given as
u(r)=(ΔP/4μL)(r^2-R^2)+(τy/μ)(r-R), where ΔP/L is the constant pressure
drop along the pipe per unit length, μ is the dynamic viscosity, r is radial
distance from the centerline, and τy is the yield stress of Bingham plastic.
Determine (a) the shear stress at the pipe wall and (b) the drag force acting
on pipe section of length L.
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