Concept explainers
(a)
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
(a)
Answer to Problem 6.69CP
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
Explanation of Solution
Given info: The expression of magnitude of resistive force exerted on a sphere is
The expression of the resistive force is,
Here,
Substitute
The expression of mass of the water droplet is,
Here,
The expression of volume of the water droplet is,
Substitute
Substitute
Thus, the mass of the water droplet is
The expression of force that acts on the water droplet is,
Here,
Compare and equate the equation (1) and the above equation.
Substitute
The contribution of the second term of
Conclusion:
Therefore, the terminal speed for water droplets falling under their own weight in air for the drop radii equal to
(b)
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
(b)
Answer to Problem 6.69CP
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
Explanation of Solution
Given info: The expression of magnitude of resistive force exerted on a sphere is
From equation (1) the expression of resistive force is,
The expression of volume of the water droplet is,
Substitute
From equation (2), the expression of mass of the water droplet is,
Substitute
From equation (3) the final equation is,
Substitute
Further solve the above equation.
Apply quadratic formula to solve the above equation.
Conclusion:
Therefore, the terminal speed for water droplets falling under their own weight in air for the drop radii equal to
(c)
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
(c)
Answer to Problem 6.69CP
The terminal speed for water droplets falling under their own weight in air for the drop radii equal to
Explanation of Solution
Given info: The expression of magnitude of resistive force exerted on a sphere is
From equation (1) the expression of resistive force is,
The expression of volume of the water droplet is,
Substitute
From equation (2), the expression of mass of the water droplet is,
Substitute
From equation (3) the final equation is,
Substitute
The contribution of the first term of
Conclusion:
Therefore, the terminal speed for water droplets falling under their own weight in air for the drop radii equal to
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Chapter 6 Solutions
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