The magnetic field is provided by electromagnets so arranged that adjacent poles have （）.

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• The line which connects the points of zero magnetic dip is（）.

  A . An agonic line B . The magnetic equator C . A magnetic meridian D . All of the above

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• The vertical component of the Earth’s magnetic field causes induced magnetism in vertical soft iron. This changes with latitude. What corrects for this coefficient of the deviation? （）

  A . The Flinders bar B . The heeling magnet C . Quadrantal soft iron spheres D . Bar magnets in the binnacle

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• The difference between magnetic heading and compass heading is called（）.

  A . variation B . deviation C . compass error D . drift

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• Magnetic dip is a measurement of the angle between the（）.

  A . geographic pole and the magnetic pole B . lubber's line and true north C . horizontal and the magnetic line of force D . compass heading and the magnetic heading

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• The compass error of a magnetic compass that has no deviation is（）.

  A . zero B . equal to variation C . eliminated by adjusting the compass D . constant at any geographical locatio

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• The coil of wire rotating in the magnetic field produces the（）.

  A . voltage B . current C . power D . frequency

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• A single vertical magnet placed underneath the compass in the binnacle is used to compensate for（）.

  A . the horizontal component of the permanent magnetism B . deviation caused by the vessel's inclination from the vertical C . induced magnetism in the horizontal soft iron D . induced magnetism in the vertical soft iro

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• If a ship is proceeding towards the magnetic equator，the uncorrected deviation due to permanent magnetism（）.

  A . increases B . remains the same C . decreases D . is unimportant and may be neglected

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• A ship under construction or major repair will acquire permanent magnetism due to（）while sitting stationary in the earth’s magnetic field.

  A . hammering and jarring B . vibration and pounding C . varying magnetic fields D . stable or permanent magnetism of the shi

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• The MOST important feature of the material used for making the binnacle of a standard magnetic compass is that it is（）.

  A . nonmagnetic B . weatherproof C . corrosion resistant D . capable of being permanently affixed to the vessel

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• The points on the earth’s surface where the magnetic dip is 90° are（）.

  A . Along the magnetic equator B . Connected by the isoclinal line C . The isopors D . The magnetic pole

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• If a magnetic compass is not affected by any magnetic field other than the Earth’s，which statement is TRUE?（）.

  A . Compass error and variation are equal B . Compass north will be true north C . Variation will equal deviation D . There will be no compass error

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• 磁场（magnetic field）

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• The vertical angle between the horizontal and the magnetic line of force is the（）.

  A . elevation B . magnetic angle C . vertical angle D . di

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• At the magnetic equator there is no induced magnetism in the vertical soft iron because（）.

  A . the lines of force cross the equator on a 0°-180°alignment B . the quadrantal error is 0° C . there is no vertical component of the Earth's magnetic field D . the intercardinal headings have less than 1&deg

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• What is the basic principle of the magnetic compass?（）

  A . Magnetic materials of the same polarity repel each other and those of opposite polarity attract B . The Earth's magnetic lines of force are parallel to the surface of the Earth C . Magnetic meridians connect points of equal magnetic variation D . The compass needle(s) will，when properly compensated，lie parallel to the isogonic lines of the Earth

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• Which statement about the Flinders bar of the magnetic compass is CORRECT（）.

  A . It compensates for the error caused by the vertical component of the Earth's magnetic field B . It compensates for error caused by the heeling of a vessel C . It compensates for quadrantal deviation D . It is only needed in equatorial water

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• 90. The angular difference between the true meridian (great circle connecting the geographic poles) and the magnetic meridian (direction of the lines of magnetic flux) is called _____.

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• 13、如果电流发生变化，磁场也将变化。 __________________________, the magnetic field will change as well.

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• Which field attribute is given the highest priority in the field selection control？ Please choose the correct answer.（)

  A.Required entry field B.Suppress C.Display D.Optional field

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• The cause of the transition of the Earth's magnetic field comes from ___.

  A．the movement deep inside the Earth B．the periodically reverses of the Earth C．the force coming from outer space D．the mechanical movement of the Earth 此题为多项选择题。

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• The Inductrack Ⅱ design can produce a very strong magnetic field even when the train runs more slowly by ______.

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• 44、一带电粒子与磁感应线成任意角度射入匀强磁场，则它作___运动； If the electric particle and the magnetic induction line are injected into the uniform magnetic field at any Angle, it will do ___ motion.

  A．直线； straight lines; B．变速率圆周； speed change rate of the circumference; C．匀速率圆周； uniform speed of the circumference; D．（D）螺线； spiral;

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