問題詳情

47. There is a laminar flow in a tube. When both the radius and length of the tube are doubled, how many times of flow resistanceis changed?
(A)


(B)


(C)


(D)


(E)

參考答案

答案：D
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)