1002 级轮机英语期末考试（A） 考试班级：1002 轮机 2.3.4.5 班 班级： 姓名： 分数： 第一部分：单选题 1.1886 The starting current of an a.c. motor is_ the rated current.A. the same as B. much larger than C. less than D. equals 2.1895 With a_ load the voltage and current are in phase.A. pure resistance B. capacitive C. inductive D. None of the above 3.1905 The emergency generator or emergency battery is connected to_ on most large ships.A. distribution boards B. section boards C. emergency switch boards D. main switch boards 4.1906 Switchboards may be of the dead-front type in which all live parts are installed behind_ and only the operation handles and instruments are on the front.A. the capstan B. the collector C. the panels D. the surface 5.1907 Remote control means that_.A. the system is manned manually B. the system is situated remotely from the operatorC. the system is controlled automatically D. all the above 6.1911 The difference between measured and desired values is called_.A. make-up B. desired value C. deviation D. set value 7.1916 Prior to any overhaul work on electric equipment, it is important to ensure the circuits are_.A. live B. dead C. excited D. on line 8. 228.Before starting an engine by air ,the engine must _ A. be turned by a turning gear for at least one minute B. be turned by a turning gear for at least two minutes C. be turned at least one complete turn D. be turned at least two complete turns 9.1924 Shore power must be_ during dock repair.A. disconnected B. switched off C. cut off D. connected 10.1927 The switchboards for a.c. systems differ from the d.c. switch gear in that the open type panels are generally_ and the dead-front switch gear is the common rule.A. permissibly B. permissible C. no permissible D. not permissible 11.1932 Current changing in direction and rising and falling in value is_.A. A.C. B. D.C. C. generator D. fresh water generator 12.1935 The separate supplies are connected in either star or delta formation. The star formation is most commonly used and requires_ slip-rings on the alternator.A. two B. three C. four D. five 13.1941 The difference between measured and desired values is calledA. offset B. error C. deviation D. set value 14.1946 After the trouble of the automatic control system has been completely eliminated, assistance is_ required.A. remained B. still C. no longer D. much mere 15.1952 The field coils_ and the armature is_. This is in fact the arrangement adopted for large, heavy duty alternators.A. stationary/rotate B. stationary/stationary C. rotate/stationary D. rotate/rotate 16.1954 An a.c. switchboard is usually_ the corresponding d.c. board because of the higher voltage and lower currents and smaller bus-bars.A. larger and heavier than B. as much as C. smaller and lighter than D. more dangerous than 17.1963 In_ the control action is independent on(of) the output.A. a closed loop control system B. an open loop control system C. a boiler control system D. a steering gear control system 18.1965 It_ for an emergency generator to require paralleling.A. is usual B. is not usual C. is necessary D. is not impossible19.1982 Which of the motors for the devices listed below is fitted with an instantaneous overload relay?A. Fan B. Pump C. Winch D. Machine tool 20.1986 An electrical device which prevents an action from occurring until all other required conditions are met is called a/an_.A. limit B. monitor C. modulator D. interlock 21.1987 A circuit breaker and a fuse have a basic similarity in that they both_.A. can be reset to energize the circuit B. should open the circuit when overloadedC. will burn out when an over current flow develops D. All of the above 22.1997 A constant output voltage from an AC generator is maintained by the_.A. prime mover governorB. exciter generator C. voltage regulator D. reverse power relay 23.2005 What will be the phase angle relationship of a six-pole, three-phase, rotating field generator _.A. 60 B. 120 C. 180 D. 360 24.2017 Copper is often used as an electrical conductor because it_. A. has high resistance at low temperatures B. has a highly polished surfaceC. is able to pass current with little opposition D. holds insulation together well 25. In a series circuit, which value will remain unchanged at all places in the circuit?A. Voltage B. Current C. Resistance D. Inductance 26.2027 The total resistance of a parallel circuit is always_.A. larger than the greatest branch resistance B. smaller than the lowest branch resistanceC. equal to the sum of the individual branch resistances D. one-half the sum of the individual branch resistances 272159 _ means the