The local atmospheric pressure in Denver, Colorado (elevation 1610 m) is 83.4 kPa. Air at this pressure and at 25’C flows with a velocity of 9 m/s over a 2.5-rn 5-rn flat plate. Determine the drag force acting on the top surface of the plate if the air flows parallel to the (a) 5-rn-long side and (b) the 2.5-m-long side.
(a)
The drag force acting on the top surface of the plate when the air flows parallel to the 5 m long side.
Answer to Problem 48P
Explanation of Solution
Given information:
Concept used:
Calculation:
The gas constant is,
For the given temperature,
Conclusion:
The drag force acting on the top surface of the plate when the air flows parallel to the 5 m long side is
(b)
The drag force acting on the top surface of the plate when the air flows parallel to the 2.5 m long side.
Answer to Problem 48P
Explanation of Solution
Given information:
Concept used:
Calculation:
The gas constant is,
For the given temperature,
Conclusion:
The drag force acting on the top surface of the plate when the air flows parallel to the 2.5 m long side is
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Chapter 11 Solutions
Fluid Mechanics: Fundamentals and Applications
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