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Your radar is set on a true motion display.Which of the following will NOT appear to move across the PPI scope ________.

  • A.Echoes from a buoy
  • B.Own ship's marker
  • C.Echo from a ship on the same course at the same speed
  • D.Echo from a ship on a reciprocal course at the same speed
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  1. Which magnetic compass corrector(s)can be set while the vessel is on a heading of magnetic north or magnetic south ________.

    • A.Quadrantal spheres
    • B.Heeling magnets
    • C.Flinders bar
    • D.Fore-and-aft magnets
  2. Which compensates for errors introduced when the vessel heels over ________.

    • A.The soft iron spheres on the arms of the binnacle
    • B.Magnets placed in trays inside the binnacle
    • C.A single vertical magnet beneath the compass
    • D.The Flinders bar
  3. When relieving the helm,the new helmsman should know the ______.

    • A.Course per magnetic steering compass
    • B.Gyro error
    • C.Variation
    • D.Maximum rudder angle previously used
  4. When a vessel changes course from one cardinal heading to another cardinal heading while adjusting the compass,which action should be taken ________.

    • A.The course change should be made rapidly to prevent transient induced magnetism while passing the intercardinal headings
    • B.After the new heading is reached,the vessel should steam on that course for at least two minutes before the adjustment
    • C.During the course change,you should gently tap the compass to remove any error caused by friction on the pivot bearing
    • D.After steadying on the new heading,the compass card should be slewed by a magnet and allowed to oscillate freely to remove any gaussin error
  5. When crossing the magnetic equator the ______.

    • A.Flinders bar should be inverted
    • B.Heeling magnet should be inverted
    • C.The quadrantal spheres should be rotated 180°
    • D.Flinders bar should be moved to the opposite side of the binnacle
  6. This induced magnetism ______ the permanent magnetism already present in the ship.

    • A.will add to
    • B.will subtract from
    • C.may add to or subtract from
    • D.will not change
  7. What is used to correct for both induced and permanent magnetism,and consequently must be readjusted with radical changes in latitude ________.

    • A.Flinders bar
    • B.Soft iron spheres
    • C.Fore-and-aft permanent magnets in their trays
    • D.Heeling magnet
  8. The most accurate method of determining gyrocompass error while underway is by ______.

    • A.Comparing the gyro azimuth of a celestial body with the computed azimuth of the body
    • B.Comparing the gyro heading with the magnetic compass heading
    • C.Determining from the chart the course made good between celestial fixes
    • D.It cannot be determined accurately at sea due to drift of unknown currents
  9. The gyrocompass error resulting from your vessel's movement in OTHER than an east-west direction is called ______.

    • A.Damping error
    • B.Ballistic deflection
    • C.Quadrantal error
    • D.Speed error
  10. The magnetism in the various structures of a ship changing as a result of cruising,vibration,or aging is termed ______.

    • A.permanent magnetism
    • B.subpermanent magnetism
    • C.induced magnetism
    • D.variable magnetism