If the electric motor driving an air compressor fails to start, the cause may be a （）.

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• Electric cargo winches have an overload safety device which normally cuts the current to the winch motor（）.

  A . after torque causes line pull to exceed the rated capacity of the winch B . before the line pull reaches the rated capacity of the winch C . when the line pull reaches the breaking strength of the fall D . before the safe working load of the fall is reached

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• If a person is unconscious from electric shock，you should first remove him from the electrical source and then（）.

  A . administer ammonia smelling salts B . check for serious burns on the body C . determine if he is breathing D . massage vigorously to restore circulatio

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• Which of the following pumps will build up a bursting pressure or stall their motors if the discharge valves are closed?（） (1) gear (2) centrifugal (3) screw

  A . （1）and（2） B . （1），（2）and（3） C . （1）and（3） D . （2）and（3）

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• The greatest detrimental effect on idle electrical equipment, such as cargo pump motors, is the（）.

  A . loss of residual magnetism B . absorption of moisture in the insulation C . insulation varnish flaking D . dirt collecting on the winding

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• If a small electric motor is immersed in salt water it should be （） (1) washed in fresh water (2) dried in an oven

  A . (1) only B . (2) only C . both (1) and (2) D . neither (1) or (2)

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• The drive motor will have a brake arranged to fail-safe, ieit will （） the load if power fails or machine is stopped.

  A . lift B . put C . take D . hold

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• Which of the following electric motors would be the safest and most reliable to use on the main deck of a vessel in foul weather conditions?（）

  A . Sealed motors B . Drip proof motors C . Enclosed motors D . Watertight motor

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• The （） compressor and its electrical motor are entirely housed in a gas-tight casing.

  A . open-type B . hermetic C . A and B D . None of the above

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• If absolutely necessary，the best way to land on a beach in a motor lifeboat is to（）.

  A . run as fast as the boat will go and keep the sea on the stern B . secure the engine，put sea anchor over the bow，put out the oars，use sweep oar and back onto beach C . go in under oars and put out the sea painter D . put the sea broadside and let the boat drift ashore

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• Electrical failures in motors are caused by the breakdown of insulation, which may be caused by （）

  A . penetration of moisture B . accumulation of dirt C . overheating D . All of the above

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• The functioning of the radiotelegraph installations for motor lifeboats and/or the portable radio apparatus for survival craft，if provided，（）with the provisions of the regulations.

  A . provided B . supplied C . complied D . divided

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• When hoisting a boat on gravity type davits using an electric motor driven winch，the davit arms should be brought up（）.

  A . to their final position with the winch operating at slow speed B . to the bar stop，and then hand cranked to their final position C . until just before they make contact with the limit switch，and then hand cranked to their final position D . to the embarkation deck，and then hand cranked to their final positio

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• Diesel engine electric starting motors generally require heavier duty motors and motors and operate at higher voltages than comparable starting motors for gasoline engines due to（）

  A . higher speed required B . flywheel-effect C . lower starting temperatures D . higher compression pressure

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• When there is a fire in a large electric motor, normally the very FIRST step is to （）

  A . secure the electric supply B . ventilate area to remove smoke C . start the fire pump and lead out hose D . apply foam

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• The primary function of an electric motor is to （）

  A . develop torque B . generate high voltages C . produce a magnetic field D . generate high electrical resistance

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• What type of electric motor is most commonly used on board ship?（）

  A . non-synchronous electric motor B . synchronous electric motor C . fully enclosed electric motor D . watertight electric motor

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• You are transferring fuel from the storage tanks to the day tanks by means of an electric fuel oil transfer pumpIf the pump motor catches fire, you would FIRST （）.

  A . secure the fuel manifold B . shut off power to the pump C . shut off the power ventilation D . spray water on the fire

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• “A centrifuge consists of an electric motor driving a vertical shaft on the top of which is mounted the bowl assembly”.According to this sentence, we can know that is mounted on the top of the vertical shaft（）

  A . a centrifuge B . an electric motor C . a bowl assembly D . a driving motor

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• The drive motor will have a brake arranged to fail-safe, i√eit will （） the load if power fails or machine is stopped.

  A . cast B . put C . hold D . let out

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• The （）, cage rotor induction motor is the first choice marine motor in most modern ships because of its electrical and mechanical simplicity.

  A . single phase B . two phase C . three phase D . four phase

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• If we want to buy furniture or electric appliances, which one is the reasonable choice?

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• Where do cars get their energy from？ For most cars, the answer is petrol. 1_____some cars use electricity. These cars have 2 _____motors that get their power from large batteries. In 3___, there are even cars that have 4_____ an electric motor and a petrol motor. These types of cars are 5_____ hybrid (混合) cars.

  Most people tend to think of electric cars as a new 6 ____, but they have been around for a long time. In the 7_____ 19th and early 20th centuries electric cars were common because the technology for petrol engines was not very advanced.But 8____ the petrol engine became easier to make and more powerful, this type of engines became the most 9 ____.Interest in electric cars was high in the l970s and 1980s because 10____ became very expensive.Recently, electric cars have again become well-liked because people want cars that pollute 11_____. Electric cars are better than petrol cars 12______ several ways. The biggest benefit is reduced pollution.In areas 13_____ there is a high percentage of electric cars, pollution is not that serious. The second benefit of electric cars is a 14 _____in the dependence on foreign oil.Several countries don’t want to 15 _____on oil from other countries. Since electric cars can run on electricity from coal or nuclear power stations, there is less need to import oil. (15分) (1)第1题最佳答案应选()(1分) A. But B. Nor C. Or D. And (2)第2题最佳答案应选()(1分) A. traditional B. common C. same D. special (3)第3题最佳答案应选()(1分) A. summary B. detail C. time D. addition (4)第4题最佳答案应选()(1分) A. all B. both C. either D. neither (5)第5题最佳答案应选()(1分) A. described B. regarded C. called D. known (6)第6题最佳答案应选()(1分) A. invention B. influence C. instrument D. intention (7)第7题最佳答案应选()(1分) A. last B. beginning C. recent D. late (8)第8题最佳答案应选()(1分) A. unless B. after C. before D. until (9)第9题最佳答案应选()(1分) A. popular B. comfortable C. difficult D. dangerous (10)第10题最佳答案应选()(1分) A. motors B. power C. cars D. oil (11)第11题最佳答案应选()(1分) A. much B. more C. less D. few (12)第12题最佳答案应选()(1分) A. by B. in C. at D. on (13)第13题最佳答案应选()(1分) A. when B. where C. what D. which (14)第14题最佳答案应选()(1分) A. start B. need C. reduction D. rise (15)第15题最佳答案应选()(1分) A. put B. hold C. rely D. keep

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• Ivan: I brought you the new Groove People CD.Dale: What good is a CD if I haven't got a CD player？ Ivan: I can bring you a CD player. Dale: What good is a CD player ifI don't even have electricity？ Ivan: ______ Dale: What good is calling the Electric Company if I haven't got a house？

  A．Why do you have so many questions？ B．what are you going to buy tomorrow？ C．Why don't you call the Electric Company？ D．Where did you buy the new CD？

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• If the guest wants to loan a electric heater what would you like to do ?

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