單項(xiàng)選擇題Current flowing in only one direction is called ()

A.alternating current
B.omnidirectional current
C.direct current
D.sinusoidal current


您可能感興趣的試卷

你可能感興趣的試題

1.單項(xiàng)選擇題Accidental grounds in a shipboard electrical system must be repaired as soon as possible as they will ()

A.result in immediate power outages
B.damage circuit breakers
C.appear on the ground detection system
D.damage insulation and may cause outages

2.單項(xiàng)選擇題Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine ()

A.slightly less than the line frequency
B.the same as the line frequency
C.slightly greater than the line frequency
D.All of the above

3.單項(xiàng)選擇題Which of the following should be the FIRST step in removing a generator from parallel operation?()

A.Trip the generator off the switchboard
B.Turn off all electrical equipment
C.Remove the load from the "off going" generator
D.Increase the cycles of the generator staying on the line

4.單項(xiàng)選擇題Electrical power is expressed in ()

A.ohms
B.volts
C.amps
D.watts

5.單項(xiàng)選擇題Which of the following materials is a good insulator?()

A.steel
B.aluminum
C.glass
D.copper

最新試題

The ISPS Code consists of a mandatory section-Part A, which shows()

題型:?jiǎn)雾?xiàng)選擇題

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?()

題型:?jiǎn)雾?xiàng)選擇題

The main purpose of port State control is not to()

題型:?jiǎn)雾?xiàng)選擇題

Which of the diesel engine components listed increase air density and helps to improve engine operating efficiency?()

題型:?jiǎn)雾?xiàng)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:?jiǎn)雾?xiàng)選擇題

For a given exhaust gas boiler, what is the quantity of its evaporation mainly determined?()

題型:?jiǎn)雾?xiàng)選擇題

()are used to digest the sewage to produce innocuous sludge in a biological sewage treatment plant.

題型:?jiǎn)雾?xiàng)選擇題

By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a()

題型:?jiǎn)雾?xiàng)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:?jiǎn)雾?xiàng)選擇題

To shut down a diesel engine after it exceeds the set maximum speed,which type of device listed should be used?()

題型:?jiǎn)雾?xiàng)選擇題