单选题The lubber’s line of a magnetic compass（）.A always shows true north directionB indicates the vessel's headingC is always parallel to the vessel's transomD is located on the compass card

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

Deviation in a compass is caused by the ______.

A.vessel’s geographic position

B.vessel’s heading

C.earth’s magnetic field

D.influence of the magnetic materials of the vessel

When an azimuth of the Sun has been taken and the deviation of the standard magnetic compass computed，the watch officer should record the results ______.

A.in the vessel's Official Logbook

B.on the compass deviation card

C.in the compass deviation log

D.on a Napier diagram

Magnetic compass deviation______．

A.varies depending upon the bearing used

B.is the angular difference between magnetic north and compass north

C.is published on the compass rose on most nautical charts

D.is the angular difference between geographic and magnetic meridians

Compass deviation is caused by ______.

A.magnetism from the earth’s magnetic field

B.misalignment of the compass

C.magnetism within the vessel

D.a dirty compass housing

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

Which magnetic compass corrector（s）CANNOT be set on a heading of magnetic east or magnetic west ________．

A.Heeling magnet

B.Flinders bar

C.Fore-and-aft magnets

D.All of the above can be set on magnetic east or magnetic west headings

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