32.當流體流入離心式泵（Centrifugal pump）時，有關流體當中能量轉換的敘述，下列何者正確？ (A)流體的動能轉換成壓力能 (B)流體的動能轉換成位能 (C)流體的壓力能轉換成動能 (D)流體的壓力能轉換成位能

10.Longitudinal vibration of propulsion shafting systems is often excited by the variable thrust developed by the propeller due to the non-uniform wake pattern in which it operates. The predominant periodic component of the thrust developed by a propeller occurs at blade-rate frequency, i.e., the number of propeller blades times the rotational frequency of the shaft. For a four-blade propeller running at 60 rev/min, what is the predominant periodic frequency that excites the longitudinal vibration of the propulsion shafting systems? (A)1 Hz (B)2 Hz (C)3 Hz (D)4 Hz

32.當流體流入離心式泵（Centrifugal pump）時，有關流體當中能量轉換的敘述，下列何者正確？
(A)流體的動能轉換成壓力能
(B)流體的動能轉換成位能
(C)流體的壓力能轉換成動能
(D)流體的壓力能轉換成位能

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