單項選擇題In a three-phase circuit, the phase voltages are ()

A.120°apart
B.160°apart
C.180°apart
D.360°apart


您可能感興趣的試卷

你可能感興趣的試題

1.單項選擇題The frequency of an alternator at a given RPM is determined by the ().

A.number of turns of wire in the armature coil
B.number of magnetic poles
C.strength of the magnets used
D.output voltage

2.單項選擇題The pushbutton on the handset of a ships sound-powered telephone must be depressed to ().

A.talk then released to listen
B.listen then released to talk
C.both talk and listen
D.ring the station being called

3.單項選擇題Which of the following statements is true concerning simple parallel resistance circuits?()

A.The total current flow equals the sum of the individual currents
B.The total current flow equals the reciprocal of the sum of the individual currents
C.The total resistance equals the sum of the individual resistance
D.The total voltage equals the sum of the individual voltages across each resistance

4.單項選擇題Which of the listed items will stop a motor due to a reduction in voltage and restart it when the voltage is restored to normal?()

A.Low voltage protection circuit
B.Non-renewable link fuse
C.Renewable link fuse
D.Low voltage release circuit

5.單項選擇題Which of the following statements concerning a simple parallel resistance circuit is correct?()

A.The voltage drop across each resistor is the same
B.The total current flow equals the reciprocal of the sum of the individual currents
C.The total resistance equals the sum of the individual resistances
D.The total voltage equals the sum of the individual voltages across each resistance

最新試題

As soon as a diesel engine has started, which of the listed engine operating parameters should be checked FIRST?()

題型:單項選擇題

The additional mark ()in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.

題型:單項選擇題

The shipboard oil pollution emergency plan will be invalid after ()

題型:單項選擇題

Which of the listed governor characteristics will greatly affect the load sharing relationship between paralleled diesel generators?()

題型:單項選擇題

If two A.C.generators are to be operated in parallel, the load is distributed evenly by()

題型:單項選擇題

The treatment of the fuel oils involves storage, heating, filtering and()

題型:單項選擇題

When does auxiliary burner of incinerator put into operation? ()Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish

題型:單項選擇題

“Insufficiency of manning or insufficiency of certification of seafarers” is an identification of a()

題型:單項選擇題

The flash point of a residual fuel oil should be used to determine the highest temperature to which oil may be heated()

題型:單項選擇題

The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the()

題型:單項選擇題