Compass 3

The property of certain metals to attract or repel items of like material or certain other metals

also can e an effect of electrical currents

Magnetism that is only present when the material is under the influence of an external field

Iron or steel which is easily magnetized by induction, but loses it magnetism when a magnetic field is removed

The ______________the iron, the longer it will maintain its magnetic property's once removed from a magnetic influence.

is the magnetism remaining after the magnetizing force is removed

Is the magnetism that remains for long periods of time without any appreciable reduction, unless is subjected to a demagnetizing force

Do the geographic poles match the magnetic poles?

the magnetic lines of force that connect the magnetic poles. These lines are irregular shaped to non-uniform distribution of magnetic in the earth surface.

Located midway between the poles

The difference between magnetic meridians and true meridians

Daily changes which are caused by the movement of the magnetic poles in an orbit having a diameter of about 50 miles

the yearly permanent changes in the earths magnetic field.

Changes in magnetism over a period of years

lines on the magnetic chart that connect points of equal variation or magnetic and having equal angles

Lines joining points of zero magnetic variation, a special case of an isogonic lines

Angle between the magnetic meridian and the axis of the compass card

Caused by the disturbing magnetic influences in the immediate vicinity of the magnetic compass

Ships are built with a ______________________heading

Ships are refitted on a ______________________heading ofsetting the deviation acquired during construction

Neutralizing of the strength of the magnetic field of a vessel

Ships take on permanent magnetic properties referred to it's _______________.

Is placed on the weather deck in a location where magnetic influences are the least.

is placed center lined and just forward of the steering wheel.

Bowl shaped container of non-magnetic materail which serves to contain the elements, a reference mark, and the fluid

The reference mark on the inside of the compass bowl used to read the direction of the ships heading

-Aluminum disk graduated in degrees

Showing cardinal and inter cardinal points

Four bundles of magnetic steel wire or bar magnets. These are attached to the compass card to supply directive force

What fluid is used in a compass?

Aluminum air-filled chamber in the center of the compass card

Designed to compensate for temperature changes attached to the bottom of the compass bowl

Permits the compass bowl to remain horizontal regardless of the vessels movement

A stand made of non-magnetic material in which the compass is mounted

Inside are trays or holders for the fore and aft magnets used for adjusting the compass

Soft Iron on both sides of the binnacle.

-Used to offset induced magnetism caused by the ships' structure, also used in adjusting the compass

Soft iron having no permanent magnetism located in a side mounted tube on the compass binnacle vertically

Located in a vertical tube directly below the center of the compass

Magnets used to steady the compass card "swing" or oscillations

Advantages of a gyro Compass

Disadvantages of a gyrocompass

The gyrocompass has how many degrees of freedom

once the gyroscope starts to spin, it will resist change in the orientation of the spin axis

If a torque or twistin force is applied to the spin axis, the axis will not turn in the direction in the direction of the torque, but will instead move in a direction perpendicular to it