Brushless generators are designed to operate without the use of_____.A.brushesB.slip ringsC.commutatorsD.all of the above
Brushless generators are designed to operate without the use of_____.
A.brushes
B.slip rings
C.commutators
D.all of the above
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But the hardware is designed to use even（）power than other schemes， making it especially appropriate for such things as RFID tags， which must work for years（）any external power source.A．most B．more C．less D．otherA．with B．without C．as D．than
When the prime movers of two paralleled generators are equipped with mechanical-hydraulic governors, and are operating within their designed range, the unit with the least amount of speed droop will .A.pick up more of any increase in loadB.pick up less of any increase in loadC.share an equal amount of any increase in loadD.drop an equal amount of any decrease in load
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Which command （without options） would you use to display how much space is available on all mounted partitions？（）
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单选题Deck foam systems，designed to protect cargo areas on tankers built after January 1，1975，must have a supply of foam-producing material to operate the system at its designed rate of foam production for（）.A15 minutes without rechargingB20 minutes without rechargingC25 minutes without rechargingD30 minutes without recharging
单选题What is TRUE of pressure/vacuum valves? （）AThey are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tankBThey should operate in advance of the pressure/vacuum breakersCThey should be kept in good working order by regular inspection and cleaningDAll of the above