单项选择题

The unit "hertz" is equivalent to （）

A.coulombs per second
B.revolutions per second
C.revolutions per minute
D.cycles per second

相关考题

When paralleling two AC generators, the frequency of th...

单项选择题When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）

A.slightly less than the oncoming generator frequency
B.the same as the bus frequency
C.slightly greater than the bus frequency
D.the same as the bus voltage

When two AC generators are being paralleled, the breake...

单项选择题When two AC generators are being paralleled, the breaker should be closed with the synchroscope pointer mating in the （）

A."slow" direction, just before the 12 o'clock position
B."fast" direction, just after the 12 o'clock position
C."fast" direction, just before the 12 o'clock position
D."slow" direction, just after the 12 o'clock position

AC voltmeters are generally calibrated to read the （）A....

单项选择题AC voltmeters are generally calibrated to read the （）

A.instantaneous voltage
B.average voltage
C.RMS voltage
D.peak voltage

船舶电气与船舶安全

The unit "hertz" is equivalent to （）