The updraft velocity of air motion.
Answer to Problem 64P
The updraft velocity of air motion is
Explanation of Solution
Given information:
The diameter of the dust particle is
Write the expression for the weight of the body.
Here, the drag force is
Write the expression for weight of the body in terms of density.
Here, the density of dust particle is
Write the expression for the drag force as per stokes law.
Here, the velocity of the dust particle is
Write the expression for the buoyant force.
Here, the density of air is
Write the expression for the volume of the dust particle.
Calculation:
Substitute
Substitute
Refer to Table A-9, “Properties of air” to obtain the values of
Substitute
Substitute
Substitute
Conclusion:
The updraft velocity of air motion is
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Chapter 11 Solutions
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