The magnetism in the various structures of a ship changing a

Permanent magnetism is caused by ______.

A.operation of electrical equipment and generators on board ship

B.the earth's magnetic field affecting the ship's hard iron during construction

C.the horizontal component of the earth's magnetic field acting on the horizontal soft iron

D.the vertical component of the earth's magnetic field acting on the vertical soft iron

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 ship

In the navigation,_______cause the shafting over load most easily

A.stopping the main engine suddenly

B.changing the main engine running direction suddenly

C.the sailing from the shallow water area to the deep water area

D.the ship's trim too much

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

The Flinders bar and the quadrantal spheres should be tested for permanent magnetism at what interval ________．

A.They are not subject to permanent magnetism; no check is necessary

B.Semiannually

C.Annually

D.Every five years

Floors aboard ship are ______．

A.also called decks

B.vertical transverse plates connecting the vertical keel with the margin plates

C.large beams fitted in various parts of the vessel for additional strength

D.found in passenger and berthing spaces only

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

say something about ship’s structures.

______ is not contained in the muster list．

A.the details of how the order to abandon ship is given

B.the details of the general emergency alarm signal，the fire alarm signal and the public address system

C.the substitutes for key persons who may become disabled

D.the various fire sections enclosed by“A”class divisions

If the vertical center of gravity (VCG) of a ship rises 1.7 feet, the righting arm (GZ) for the various angles of inclination will ______.

A.decrease

B.increase

C.remain unchanged

D.be changed by the amount of GG’ x cosine of the angle