Which of the following statements represents an advantage of an electromagnetic clutch？
A. Large misalignments can be tolerated between the shaft and engine coupling
B. Slip is held to a minimum when reversing shaft rotation
C. Engine torsional vibrations to the driven shaft are eliminated
D. It aids in maintaining power factor
When the ship is going to enter into the harbor, ____.
A. change from heavy fuel oil to diesel oil for main engine
B. pumping out bilge water
C. change sea chest from high level one to lower level one
D. test emergency generator
In reducing engine speed to an efficient propeller speed by the use of reduction gears, _______.
A. speed and torque are both reduced
B. speed is reduced and torque remains unchanged
C. speed is reduced and torque is increased
D. speed is sometimes unchanged while torque is increased
Which of the listed devices may be used as a digital device？
A. variable resistor
B. diode
C. strain gauge
D. thermistor
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