試題詳解

9. Cough can increase the initial horizontal velocity of the droplets, allowing the longer travel distance of the droplets. Usually, the average velocity of cough flow is 10 m/s. Please calculate the Reynolds number of the cough flow. Assume the opening of the mouth is 1 cm in diameter. Choose the closest answer.
(A)500,
(B) 1000,
(C) 3000,
(D) 5000,
(E) 6000