35.按船級協會之規定，錨機應能以動力起落錨，而左右舷兩錨同時捲揚上升的平均速率，不得小於每分鐘多少公尺？ (A)5 (B)7 (C)9 (D)11

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

35.按船級協會之規定，錨機應能以動力起落錨，而左右舷兩錨同時捲揚上升的平均速率，不得小於每分鐘多少公尺？
(A)5
(B)7
(C)9
(D)11

相關試題

相關試卷

35.按船級協會之規定，錨機應能以動力起落錨，而左右舷兩錨同時捲揚上升的平均速率，不得小於每 分鐘多少公尺？ (A)5 (B)7 (C)9 (D)11

相關試題

相關試卷

35.按船級協會之規定，錨機應能以動力起落錨，而左右舷兩錨同時捲揚上升的平均速率，不得小於每分鐘多少公尺？
(A)5
(B)7
(C)9
(D)11