Before a magnetic compass is adjusted certain correctors mus

Before sailing，mariners on duty shall check the headings of magnetic compass by comparison with ______.

A.ship's clock

B.engine movement recorder

C.repeaters

D.navigation lights

Deviation is the angle between the ______.

A.true meridian and the axis of the compass card

B.true meridian and the magnetic meridian

C.magnetic meridian and the axis of the compass card

D.axis of the compass card and the degaussing meridian

Which one of the followings is incorrect about magnetic compass?______.

A.The magentic compass is compulsory on my vessel

B.The magentic compass is prone to error

C.The magentic compass is always placed inside steel constructions

D.The magentic compass needs to be calibrated to compensate for local magnetic distortion

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

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

Before a magnetic compass is adjusted certain correctors must be checked to ensure that they are free of permanent magnetism．These correctors are the ______．

A.Fore-and-aft and athwartships magnets

B.Dip needle and heeling magnet

C.Heeling magnet and Flinders bar

D.Flinders bar and quadrantal spheres

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

On a nautical chart，the inner ring of a compass rose indicates ______.

A.true directions

B.compass error

C.deviation

D.magnetic directions

Magnetic heading differs from compass heading by______．

A.compass error

B.true heading

C.variation

D.Deviation