問題詳情

42. Tension is maintained in a string as in the figure. The observed wave speedis v = 24 m/s when the suspended mass is m = 3 kg. What is the wave speedwhen the suspended mass is m = 1 kg? (Gravitational acceleration g = 10m/s2)


(A) 4.6 m/s
(B) 5.7 m/s
(C) 8.0 m/s
(D) 11.3 m/s
(E) 13.9 m/s

參考答案

答案：E
難度：計算中-1
書單：沒有書單，新增

用户評論

【面試倒楣鬼-22幸運上後西】評論

v = √(T/u)  , 此題u不變化, T = mg,v1 = 24 =√(3g/u) , v2 = √(1g/u)  = v1/√3 = (E) 13.9 m/s