Practice Impact Of Reynolds Number And Surface Roughness (17.6.3)

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8 questions

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Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
What is the formula for calculating Reynolds number?
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Identify the terms involved in the equation.
Question 2.
What does a high Reynolds number indicate about flow?
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Think about flow characteristics.
3Question 3.
What does a Reynolds number greater than 4000 indicate?
- Laminar Flow
- Transitional Flow
- Turbulent Flow
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Relate the number to flow regime definitions.
4Question 4.
True or False: A higher surface roughness always increases drag.
- True
- False
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Think of examples in design contexts.
Question 5.
Evaluate the drag force on an object with Cd = 0.7, A = 2 m², ρ = 1.225 kg/m³, and v = 30 m/s.
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Use the drag force formula correctly.
Question 6.
A smooth sphere has a Reynolds number of 2500. Discuss flow characteristics and if you expect high or low drag.
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Relate Re values back to flow characteristics.

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