1. Strong winds during a thunderstorm suspend dust particles in the air, sometimes leading to dust storms. A dust particle 50 µm in diameter and density 1.7 g/cm³ has reached a height of 250 m after a wind gust. 1 - Assume that the motion of air around the particle is in the creeping flow regime. 2 - Assume that the particle reaches its vertical terminal velocity instantaneously. (b) Verify that the two assumptions are valid. To verify assumption 2, write the vertical component of Newton’s second law for the particle motion (F = ma) and use it to calculate the time that the particle needs to reach 99% of its terminal velocity. %3D

1. Strong winds during a thunderstorm suspend dust particles in the air, sometimes leading to dust storms. A dust particle 50 µm in diameter and density 1.7 g/cm³ has reached a height of 250 m after a wind gust. 1 - Assume that the motion of air around the particle is in the creeping flow regime. 2 - Assume that the particle reaches its vertical terminal velocity instantaneously. (b) Verify that the two assumptions are valid. To verify assumption 2, write the vertical component of Newton’s second law for the particle motion (F = ma) and use it to calculate the time that the particle needs to reach 99% of its terminal velocity. %3D

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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