Electrical circuits are protected against overheating by means of a/an _______.A.circuit breakerB.amplifierC.diode （二极管）D.capacitor
Electrical circuits are protected against overheating by means of a/an _______.
A.circuit breaker
B.amplifier
C.diode （二极管）
D.capacitor
相关考题：
●Frame. Relay is simplified form. of (71) ，similar in principle to (72) ，in which synchronous，frames of data are routed to different destinations depending on header information．Packets are routed throught one or more Virtual Circuits known as (73) .Most Virtual Circuits are (74) ，which means that the network provider sets up all DLCI connections at subscription time． (75) are also part of the Frame. Relay specification．They privide a link that only lasts only as long as the session．(71) A．Datagram SwitchingB．Datagram RoutingC．Packet SwitchingD．packet Routing(72) A．X．21B．X．25C．X．28D．X．29(73) A．DLCIsB．HDLCsC．SDLCsD．DLs(74) A．Permanent CircuitsB．Permanent Virtual CircuitsC．Switched Virtual CircuitsD．Switching Circuits(75) A．Permanent CircuitsB．Permanent Virtual CircuitsC．Switched Virtual CircuitsD．Switched Circuits
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Fusible plugs are installed in fire-tube boilers to _____.A.provide a means of draining the boilerB.warn the engineer of low water levelC.cool the crown sheet at high firing ratesD.open the burners electrical firing circuits
Frame. Relay is simplified form. of(71), similar in principle to(72), in which synchronous, frames of data are routed to different destinations depending on header information.Packets are routed throught one or more Virtual Circuits known as(73)Most Virtual Circuits are(74), which means that the network provider sets up all DLCI connections at subscription time.(75)are also part of the Frame. Relay specification. They privide a link that only lasts only as long as the session.A．Datagram SwitchingB．Datagram RoutingC．Packet SwitchigD．packet Routing
What are two benefits of the modular design of the Junos OS?() A. Each module uses application-specific integrated circuits (ASICs).B. Each module runs in its own protected memory space.C. Each module can be individually restarted.D. Each module is supported across all Junos platforms.
Frame. Relay is simplified form. of(71), similar in principle to(72), in which synchronous, frames of data are routed to different destinations depending on header information . Packets are routed throught one or more Virtual Circuits known as(73). Most Virtual Circuits are(74),which means that the network provider sets up all DLCI connections at subscription time.(75)are also part of the Frame. Relay specification . They privide a link that only lasts only as long as the session.A．Datagram SwitchingB．Datagram RoutingC．Packet SwitchingD．packet Routing
The part of the shipboard electrical system used to control the distribution of power to the branch circuits, is the ______.A.bridge control panelB.disconnect linksC.main switchboardD.governor relay box
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The item ______ is not the advantage of the hydraulic winch．A.less jerky startsB.less jerky stopsC.overheating worriesD.none of the overheating worries
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What are two benefits of the modular design of the Junos OS?（）A、Each module uses application-specific integrated circuits (ASICs).B、Each module runs in its own protected memory space.C、Each module can be individually restarted.D、Each module is supported across all Junos platforms.
What type of protection is implemented when the DBA issues the ALTER DATABASE SET STANDBY DATABASE PROTECTED； command？（）A、The standby database is protected against write operations. B、The primary database is protected against write operations. C、The primary database is protected against data loss and data divergence. D、The standby database is protected against data loss and data divergence.
单选题When electrical equipment is involved in a fire，the stream of dry chemicals should be（）.Aaimed at the source of the flamesBfogged above the equipmentCshot off a flat surface onto the flamesDused to shield against electrical shock
单选题The part of the shipboard electrical system used to control the distribution of power to the branch circuits, is the （）.Abridge control panelBdisconnect linksCgovernor relay boxDmain switchboard
单选题What type of protection is implemented when the DBA issues the ALTER DATABASE SET STANDBY DATABASE PROTECTED； command？（）AThe standby database is protected against write operations. BThe primary database is protected against write operations. CThe primary database is protected against data loss and data divergence. DThe standby database is protected against data loss and data divergence.
单选题Which statement concerning reserve sources of energy for GMDSS is FALSE（）.AWhile the ship is at sea，there must be available at all times a supply of electrical energy sufficient to operate the radio installations and to charge any batteries used as part of a reserve source of energyBBoth the VHF and MF/HF installations must be simultaneously suppliedCA means of ensuring a continuous supply of electrical power must be provided to all GMDSS equipment that could be affected by an interruption in powerDIf a UPS or equivalent is used to supply power to the ship's GPS receiver or other source of positional information，a means must be provided to ensure the continuous supply of the information in the event of a failure to the ship's main or emergency source of power
单选题Electric generators can be protected against overload（）.AWith switchesBWith a governor on the engineCWith fuses or circuit breakersDBy using heavy wire
单选题Fusible plugs are installed in fire-tube boilers to （）.Aprovide a means of draining the boilerBwarn the engineer of low water levelCcool the crown sheet at high firing ratesDopen the burners electrical firing circuits
单选题Which of the following statements represents the FIRST precaution to be taken prior to working on any installed electrical component （）AWear rubber gloves and bootsBUse only approved non-conducting toolsCGround the case of the machine before beginning any repairsDOpen the supply circuits and tag the switches
多选题What are two benefits of the modular design of the Junos OS?（）AEach module uses application-specific integrated circuits (ASICs).BEach module runs in its own protected memory space.CEach module can be individually restarted.DEach module is supported across all Junos platforms.
单选题Electric circuits are protected against overloads and short circuits by means of a/an （）.Acircuit breakerBamplifierCdiodeDcapacitor
单选题When two DC generators operate in parallel, they are protected against motorizing by（）Ablow out coilsBgovernor relayCunder voltage tripsDreverse current trips
单选题Electrical circuits are protected against overheating by means of a/an （）.Acircuit breakerBamplifierCdiodeDcapacitor
单选题Vessel underway means that a vessel is（）.Aon the wayBat anchorCmade fast to a terminalDmoving against water
单选题An ABC dry chemical fire extinguisher would be LEAST effective against a fire in（）.Aa mattressBspilled liquids such as oil or paintChigh voltage electrical gearDa trash can