Engineering Board Exam Reviewer · Environmental Engineering · hard
Using Stokes' law, what is the settling velocity of a discrete particle 0.05 mm in diameter with a density of 2650 kg/m3 in water at 20 ° C ( = 1000 kg/m3, = 0.001 Pa· s)?
- 8.99 mm/s
- 2.25 mm/s
- 44963 mm/s
- 1.12 mm/s
Answer
B. 2.25 mm/s
Solution
vs = g( p - )d2/(18 ) = 9.81(1650)(5 × 10-5)2/(0.018) = 0.002248 m/s = 2.25 mm/s.
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