36.為環境保護的考量，含有四氯化碳之溶劑，不可以使用於何種用途？ (A)冷凍劑 (B)冷卻劑 (C)冷凝劑 (D)加熱劑

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

36.為環境保護的考量，含有四氯化碳之溶劑，不可以使用於何種用途？
(A)冷凍劑
(B)冷卻劑
(C)冷凝劑
(D)加熱劑

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