The permanent magnetism of a vessel may change in strength due to().
A、the nature of the cargo being carried
B、changes in heading
C、major structural repair
D、All of the above
A、the nature of the cargo being carried
B、changes in heading
C、major structural repair
D、All of the above
A、A.hammering and jarring B、B.vibration and pounding C、C.varying magnetic fields D、D.stable or permanent magnetism of the ship
A、induced magnetism in the vessel's horizontal soft iron B、change in the magnetic field when the vessel inclines from vertical C、permanent magnetism of the vessel D、magnetic fields caused by electrical currents in the vicinity
A、induced magnetism in vertical soft iron B、induced magnetism in horizontal soft iron C、permanent magnetism in ship's steel D、vessel's inclination from the vertical
A、Induced magnetism in vertical soft iron B、Induced magnetism in horizontal soft iron C、Permanent magnetism in ship's steel D、Vessel's inclination from the vertical
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 iron
A、A.They are not subject to permanent magnetism; no check is necessary B、B.Semiannually C、C.Annually D、D.Every five years
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、being moored for a long time on one heading B、being struck by lighting C、steaming from the north magnetic hemisphere to the south magnetic hemisphere D、loading a homogenous magnetic cargo such as steel plate,iron bars,etc