单选题Most tachometers measure the speed of rotation of a spinning shaft or wheel in terms of revolutions per minute.A pumping B wavering C floating D whirling

题目
单选题
Most tachometers measure the speed of rotation of a spinning shaft or wheel in terms of revolutions per minute.
A

pumping      

B

wavering      

C

floating  

D

whirling

相似考题

1.RPMA.revolutions per minuteB.revolutions per mileC.revolutions per monthD.very personal matter

2.The main function of a processor is to(68)and carry out instructions which usually consist of operation and(69). The term to measure the speed of the processor is called a Megahertz(MHz), which means million(70)per second.A．translateB．interpretC．describeD．store

3.“Full speed ahead” and “Full speed astern” are ______ given by the officers or the pilots.A.sailing ordersB.speed ordersC.wheel ordersD.telegraph orders

4.The mode of control employed by an alarm circuit is aA.two position controlB.single speed floating controlC.proportional speed floating controlD.reset control

更多“单选题Most tachometers measure the speed of rotation of a spinning shaft or wheel in terms of revolutions per minute.A pumping B wavering C floating D whirling”相关问题

  • 第1题：

    共用题干
    Learn about Light
    1 .Ancient civilizations were amazed by the existence of light for thousands of years. The Greek philosophers believed that light was made up of countless,tiny particles that enter the human eye and create what we call vision. However,Empedocles and a Dutch scientist named Christian Huygens believed that light was like a wave. According to them,light spread out and travelled like a straight line. This theory was accepted during the 19th century.
    2 .In 1905,Albert Einstein published a research paper in which he explained what is re-ferred to as the photoelectric effect. This theory explains that particles make up light.The particles Einstein was referring to are weightless bundles（束）of electromagnetic（电磁）energy called photons（光子）.Today,scientists agree that light has a dual（二重）nature一it is part particle and part wave. It is a form of energy that allows us to see things around us.
    3 .Things that give off light are known as sources of light. During the day,the primary source of light is the sun. Other sources of light include stars,flames,flashlights,street lamps and glowing gases in glass tube.
    4 .When we draw the way light travels we always use straight lines. This is because nor-mally light rays travel in a straight line. However,there are some instances that can change the path and even the nature of light. They are reflection,absorption,interference（干扰）, etc.
    5 .Physicists have attempted to measure the speed of light since the early times. In 1849, Hippolyte Fizeau conducted an experiment by directing a beam of light to a mirror located kilometers away and placed a rotating cogwheel（旋转齿轮）between the beam and the mirror. From the rate of rotation of the wheel,number of wheel's teeth and distance of the mirror,he was able to calculate that the speed of light is 313 million meters per second. In a vacuum（真空）,however,the speed of light is 299,792,458 meters per second. This is about a million times faster than the speed of an airplane.

    Hippolyte Fizeau conducted an experiment to measure______.
    A: sources of light
    B: the speed of light
    C: the path of light
    D: a straight line
    E: a beam of light
    F: a form of energy

    答案：B
    解析：
    该概括大意与完成句子所选的阅读材料为记述文，段落主题相对于论述文而言较松散，因此记述文中的段落大意往往需要考生根据自己的理解而归纳概括出来。解答概括大意题的技巧往往派不上用场。第二段主要讲述现代科学家认同了爱因斯坦的光电效应理论。因此可以判断A选项“当今人们如何解释光的性质”正确。
    第三段第一句“Things that give off light are known as sources of light.”就点明主旨，发光的物体是光源。所以B选项“什么是光源？”正确。
    第四段主要讲述光传播的问题，所以D选项“光是如何传播的”正确。
    第五段的关键字是speed of light，光速。所以C选项“物理学家如何测量光的速度”正确。
    题干意为“人们可以看见物体是因为光……。“从第二段最后一句可知，人们看见物体是因为光是一种能量。所以F项a form of energy正确的。
    题干意为“星星、火焰、手电筒都是……的例子。”第三段“Other sources of light include stars , flames , flashlights...”说明，这些都是光源的例子。所以A选项sourcesof light是正确的。
    题干意为“某些情况下，如反射和吸收可以改变……。”第四段中“there are some instances that can change the path and even the nature of light.They are reflection,ab-sorption , interference , etc.”这说明有一些情况可以改变光的路径。所以C选项the path of light是正确的。
    题干意为“Hippolyte Fizeau做了一个刚试……的实验。”文中最后一段 “Hippolyte Fizeau conducted an experiment by directing a beam of light to a mirror...he was able to calculate that the speed of light...”可知Hippolyte Fizeau通过实验计算出了光速。所以B选项是正确的。

  • 第2题：

    共用题干
    Learn About Light

    1 Ancient civilizations were amazed by the existence of light for thousands of years?The Greek philoso-
    phrrs believed that light was made up of countless,tiny particles that enter the human eye and create what
    we call vision.However,Empedocles and a Dutch scientist named Christian Huygens believed that light wag
    like a wave.According to them,light spread out and travelled like a straight line.This theory was accepted
    during the 19th century.
    2 In 1905,Albert Einstein published a research paper in which he explained what is referred to as the
    photoelectric effect.This theory explains that particles make up light.The particles Einstein was referring to
    are weightless bundles（束）of electromagnetic（电磁）energy called photons（光子）.Today,scientists agree
    that light has a dual（二重）nature一it is part particle and part wave. It is a form of energy that allows us to
    see things around us.
    3 Things that give off light are known as sources of light.During the day,the primary source of light is
    the sun.Other sources of light include stars,flames,flashllights,street lamps and glowing gases in glass
    tube.
    4 When we draw the way light travels we always use straight lines.This is because normally light rays
    travel in a straight line.However,there are some instances that can change the path and even the nature of
    light. They are reflection,absorption,interference（干扰）,etc.
    5 Physicists have attempted to measure the speed of light since the early times.In 1849,Hippolyte
    Fizeau conducted an experiment by directing a beam of light to a mirror located kilometers away and placed
    a rotating cogwheel（旋转齿轮）between the beam and the mirror. From the rate of rotation of the wheel,
    number of wheel'S teeth and distance of the mirror,he was able to calculate that the speed of light is 313
    million meters per second.In a vacuum（真空）,however,the speed of light is 299,792,458 meters per
    second.This is about a million times faster than the speed of an airplane.

    Hippolyte Fizeau conducted an experiment to measure_________.
    A:sources of light
    B:the speed of light
    C:the path of light
    D:a straight line
    E:a beam of light
    F:a form of energy

    答案：B
    解析：
    第二段前半部分介绍了爱因斯坦的光电效应理论，后半部分则介绍了现代科学家对于 光的看法：他们认为光具有二重性。
    第三段主要讲述了光源的定义和常见的光源，故选B。
    第四段主要讲述了光的传播方式以及影响光的传播方式和性质的因素，故选D。
    第五段以Flippolvte Fizeau为例，介绍了物理学家是如何测定光速的，故选C。
    文章第一段中只提到光像一条直线一样传播，而并非说光是一条直线。另外，由第二段 最后一句话“it is a form of energy that allows us to see things around us.”可知，光是一种能让我 们看到周围事物的能量，故选F。
    山第三段的最后一句话“Other sources of light include stars, flames, flashlights, street lamps and glowing gases in glass tube.”可知，应选A。
    由第四段最后两句话可知，一些因素会影响光的传播路径，这些因素包括光的反射、光 的吸收和光的干扰，故选C。
    由第五段的实例可知,Hippolyte Fizcau是用一束光测出了光的速度，故选B。第4部分；阅读理解第一篇 本篇文章主要讲述了石墨烯对于将未电子学发展的重要性以及人们可用一种简单的方式发 现石、墨烯。

  • 第3题：

    RPM（）

    • A、revolutions per minute
    • B、revolutions per mile
    • C、revolutions per month
    • D、very personal matter

    正确答案:A

  • 第4题：

    An encoder sensor typically detects：（）

    • A、paper position.
    • B、shaft rotation.
    • C、magnetic flux.
    • D、laser beam strength.

    正确答案:B

  • 第5题：

    单选题
    Which of the following statements is true concerning centrifugal pumps?（）
    A

    They are particularly suited for pumping high viscosity fluids

    B

    They are started with the discharge valve opened

    C

    The flow of liquid is developed by imparting energy due to the rotation of an impeller

    D

    They are always mounted in a horizontal position


    正确答案： A
    解析： 暂无解析

  • 第6题：

    单选题
    The main function of tie rods in the construction of large, low speed diesel engines is to（）.
    A

    stiffen the bedplate in way of the main bearings to increase the engines longitudinal strength

    B

    accept most of the tensile loading that results from the firing forces developed during operation

    C

    mount the engine frame securely to the hull to prevent shaft coupling misalignment

    D

    connect the crosshead solidly to the piston rod


    正确答案： C
    解析： 暂无解析

  • 第7题：

    单选题
    The mode of control employed by an alarm circuit is a （）
    A

    two position control

    B

    signal speed floating control

    C

    proportional speed floating control

    D

    reset control


    正确答案： C
    解析： 暂无解析

  • 第8题：

    单选题
    During maneuvering operations for a direct reversing large, low-speed, main propulsion diesel engine, which of the following actions is used to stop the shaft from turning prior to reversing the engine rotation?（）
    A

    Flywheel inertia

    B

    Admission of starting air

    C

    The way of the vessel

    D

    securing of fuel to the cylinders


    正确答案： C
    解析： 暂无解析

  • 第9题：

    单选题
    According to the passage, which of the following statements is true?
    A

    The imaging techniques not only measure nerve-cell activity but also the extra flow of blood that surges to the most active brain areas.

    B

    The imaging techniques do not measure nerve-cell activity directly, but measure the flow of blood that surges to the most active brain areas.

    C

    The imaging techniques measure the extra flow of blood that surges to the most active brain areas.

    D

    The imaging techniques measure all the activities of the living brain.


    正确答案： D
    解析：
    是非题。文章第二段主要讲述imaging techniques，该段最后一句指出“they measure the extra flow of blood that surges to the most active brain areas.”（这两种成像技术测量的是涌到大脑最活跃部分的血液的额外流量），对应选项C。

  • 第10题：

    单选题
    You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. You create a custom control named Wheel. You need to ensure that the Speed property of Wheel can be animated. What should you do?（）
    A

     Inherit the DependencyObject class.

    B

     Declare the Speed property as a dependency property.

    C

     Declare an animation of the Speed property from within the code-behind file.

    D

     Implement the System.Windows.Media.Animation.IAnimatable interface with the Wheel class.


    正确答案： D
    解析： 暂无解析

  • 第11题：

    单选题
    The governor brake shall be capable of controlling the speed of lowering a fully equipped lifeboat with its complement of persons on board at（）.
    A

    safe speed only specified

    B

    not less than 120 feet per minute

    C

    not more than 120 feet per minute

    D

    not more than 90 feet per minute


    正确答案： A
    解析： 暂无解析

  • 第12题：

    单选题
    With four-stroke engines, it takes four revolutions of the crank shaft to make （） power stroke(s).
    A

    1

    B

    2

    C

    4

    D

    8


    正确答案： B
    解析： 暂无解析

  • 第13题：

    共用题干
    Learn about Light
    1 .Ancient civilizations were amazed by the existence of light for thousands of years. The Greek philosophers believed that light was made up of countless,tiny particles that enter the human eye and create what we call vision. However,Empedocles and a Dutch scientist named Christian Huygens believed that light was like a wave. According to them,light spread out and travelled like a straight line. This theory was accepted during the 19th century.
    2 .In 1905,Albert Einstein published a research paper in which he explained what is re-ferred to as the photoelectric effect. This theory explains that particles make up light.The particles Einstein was referring to are weightless bundles（束）of electromagnetic（电磁）energy called photons（光子）.Today,scientists agree that light has a dual（二重）nature一it is part particle and part wave. It is a form of energy that allows us to see things around us.
    3 .Things that give off light are known as sources of light. During the day,the primary source of light is the sun. Other sources of light include stars,flames,flashlights,street lamps and glowing gases in glass tube.
    4 .When we draw the way light travels we always use straight lines. This is because nor-mally light rays travel in a straight line. However,there are some instances that can change the path and even the nature of light. They are reflection,absorption,interference（干扰）, etc.
    5 .Physicists have attempted to measure the speed of light since the early times. In 1849, Hippolyte Fizeau conducted an experiment by directing a beam of light to a mirror located kilometers away and placed a rotating cogwheel（旋转齿轮）between the beam and the mirror. From the rate of rotation of the wheel,number of wheel's teeth and distance of the mirror,he was able to calculate that the speed of light is 313 million meters per second. In a vacuum（真空）,however,the speed of light is 299,792,458 meters per second. This is about a million times faster than the speed of an airplane.

    Paragraph 3______
    A: How Is the Nature of Light Explained Today?
    B: What Are Sources of Light?
    C: How Did Physicists Measure the Speed of Light?
    D: How Does Light Travel?
    E: How Did People Think of Light Years Ago?
    F: What Causes a Shadow?

    答案：B
    解析：
    该概括大意与完成句子所选的阅读材料为记述文，段落主题相对于论述文而言较松散，因此记述文中的段落大意往往需要考生根据自己的理解而归纳概括出来。解答概括大意题的技巧往往派不上用场。第二段主要讲述现代科学家认同了爱因斯坦的光电效应理论。因此可以判断A选项“当今人们如何解释光的性质”正确。
    第三段第一句“Things that give off light are known as sources of light.”就点明主旨，发光的物体是光源。所以B选项“什么是光源？”正确。
    第四段主要讲述光传播的问题，所以D选项“光是如何传播的”正确。
    第五段的关键字是speed of light，光速。所以C选项“物理学家如何测量光的速度”正确。
    题干意为“人们可以看见物体是因为光……。“从第二段最后一句可知，人们看见物体是因为光是一种能量。所以F项a form of energy正确的。
    题干意为“星星、火焰、手电筒都是……的例子。”第三段“Other sources of light include stars , flames , flashlights...”说明，这些都是光源的例子。所以A选项sourcesof light是正确的。
    题干意为“某些情况下，如反射和吸收可以改变……。”第四段中“there are some instances that can change the path and even the nature of light.They are reflection,ab-sorption , interference , etc.”这说明有一些情况可以改变光的路径。所以C选项the path of light是正确的。
    题干意为“Hippolyte Fizeau做了一个刚试……的实验。”文中最后一段 “Hippolyte Fizeau conducted an experiment by directing a beam of light to a mirror...he was able to calculate that the speed of light...”可知Hippolyte Fizeau通过实验计算出了光速。所以B选项是正确的。

  • 第14题：

    Consonant articulation is relatively easy to feel and as a result is most conveniently described in terms of ( ) and manner of articulation.

    A.place
    B.speed
    C.power
    D.time

    答案：A
    解析：
    考查语音学。辅音发音相对来说更加容易被感觉到，因此研究者根据发音位置和发音方式对辅音进行了分类，

  • 第15题：

    What is the meaning “speed is not of primary importance”?（）

    • A、Speed is important          
    • B、Speed is not the most important
    • C、Speed is mainly important    
    • D、Speed is first importan

    正确答案:B

  • 第16题：

    You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. You create a custom control named Wheel. You need to ensure that the Speed property of Wheel can be animated. What should you do?（）

    • A、 Inherit the DependencyObject class.
    • B、 Declare the Speed property as a dependency property.
    • C、 Declare an animation of the Speed property from within the code-behind file.
    • D、 Implement the System.Windows.Media.Animation.IAnimatable interface with the Wheel class.

    正确答案:B

  • 第17题：

    单选题
    （） connected to the moving tiller will bring the floating lever pivot and the lever into line at right angles to the screw shaft axis.
    A

    A cut-off lever

    B

    A swivel block

    C

    A cross-head

    D

    A driving gear


    正确答案： C
    解析： 暂无解析

  • 第18题：

    单选题
    An aneroid barometer is an instrument（）.
    A

    used to measure the speed of wind

    B

    in which the pressure of the air is measured

    C

    that tells which direction a storm is coming from

    D

    used to measure the height of waves


    正确答案： A
    解析： 暂无解析

  • 第19题：

    单选题
    Rotation of the steering wheel on the navigation bridge initiates oil pressure being applied to the steering gear rams by （）.
    A

    regulating the oil flow with the six-way valve

    B

    moving the automatic differential valve

    C

    moving the receiving tele-motor which regulates the two-way valve

    D

    varying the angle of a tilting box or eccentricity of a floating ring


    正确答案： C
    解析： 暂无解析

  • 第20题：

    单选题
    Which of the terms listed below represents the operational speed at which excessive engine vibration is created?（）
    A

    Non-harmonic speed

    B

    Critical speed

    C

    Maximum speed

    D

    Design maximum speed


    正确答案： B
    解析： 暂无解析

  • 第21题：

    单选题
    Aboard damaged vessels，the MOST important consideration is preserving（）.
    A

    bilge pumping capacity

    B

    reserve buoyancy

    C

    level attitude

    D

    instability


    正确答案： C
    解析： 暂无解析

  • 第22题：

    单选题
    Most often （） is attached to the engine-propeller shaft for efficient electric power generation.
    A

    a variable-speed AC generator

    B

    a fixed-speed AC generator

    C

    an air blower

    D

    a DC generator


    正确答案： C
    解析： 暂无解析

  • 第23题：

    单选题
    The vessel is at a speed of 16（）.
    A

    kilometers per hour

    B

    miles per hour

    C

    revolution per minute

    D

    meters per hour


    正确答案： A
    解析： 暂无解析

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