Plan and conduct passage - Compasses Magnetic and Steering Control

How often should the magnetic compass error be checked?. Once a watch and after a major course alteration. Twice a day.

Precession in relation to a free gyroscope is... the geographic and magnetic meridians. the geographic meridian.

Magnetic variation changes its value with ... the vessel's position on the earth. the vessel's trim or heel.

When soft iron is induced by the earth's magnetism..... there is said to be a red pole at the end directed towards the north. the pales are said to be.

lf a ship has permanent magnetism with a blue pole to port, the deviation caused will be... zero on east and west, west on northerly, east on southerly courses. east on westerly courses.

The deviation of a compass produced by a disturbing magnet varies... inversely with the cube of the distance from the magnet. inversely with the distance.

Latitude error means that, in the northern hemisphere, the north end of a gyro compass (damped in tilt) settles... to the east of the meridian and above the horizontal. to the west of the meridian.

Damping in tilt in a gyro compass produces... an error which varies with latitude. an error.

Heeling error is at its maximum when the courses are... north or south. .

Who is authorised to carry out repairs to a ship's magnetic compass?. Only a certified compass adjuster. The Master.

The principie of a fibre-optic "gyro" compass relies on... Three fibre-optic rings, mounted on a platform, which sense the rotations of the platform dueto ship and earth movement. the rotations of the earth movement.

A gyro compass on a high-speed craft often takes time to settle correctly when altering course. What causes this problem?. The change in the (large) value of the latitude course and speed error when altering course. speed error altering course.

Latitude, course and speed error of a gyro compass... applies to all gyro compasses. gyro compasses.

From those listed, which of the statements about magnetic variation is true?. The value of variation at a place changes slowly. The value changes slowly.

How many degrees are there in each point of the compass?. 11.25. 1.

In what direction (approximately) does the axis of the gyro compass wheel point?. True North. Magnetic North.

Free gyroscopes are turned into gyro compasses by utilising... gravity. speed.

Compass error is... the angle between magnetic compass and true north. true north.

What is meant by "retentive magnetism" with regard to a ship's magnetic compass?. The ship retains induced magnetism if the ship has been heading in the same direction for a considerable period. The correctors retain magnetism.

What is the main advantage of a liquid compass over a dry card compass?. lt is steadier than a dry card compass. lt is more easily adjusted.

From those listed, which of the statements about magnetic variation is NOT true?. Variation is at its maximum value at the magnetic equator. Variation angle between true and magnetic.

Curves on charts showing values of equal variation are called... isogonic. ..

lf the axis of a free gyroscope on the equator is horizontal, the northerly end of the spin axis will... tilt up if to the east of the meridian. drift west.

When a force is applied at right angles to the spin axis of a free gyroscope, the axis moves... at 90º to the torque in the direction of the spin. 180°.

lf a ship is built in a yard while heading south, the pales of permanent magnetism will be... blue to the bow and red to the stern. northern hemisphere.

A ship which has discharged cargo using electromagnets does not necessarily have to have the magnetic compass readjusted. Why not?. Because any induced magnetism will probably decay fairly quickly. Because induced magnetism.

lf a ship has permanent magnetism with a blue pole forward, the deviation caused will be... zero on north and south, east on easterly, west on westerly courses. .

lf a ship is built in a yard while heading east, the pales of permanent magnetism will be... red to port and blue to starboard. red -blue.

How many points of the compass are there?. 32. 0.

The effect of gravity control makes the axis of the gyroscope ... move anticlockwise around a central position in an ellipse. move in an ellipse.

From those listed, which is NOT a way of destroying magnetism?. Placing another magnet next to it with unlike pales together. Heating the magnet.

Who is legally responsible for the maintenance of the ship's magnetic compass?. The owner and Master jointly. An officer especially.

A magnetic compass is subject, if certain objects are placed nearby, to interference which may affect the heading shown. From those listed, which is NOT likely to do so?. Coins (money). mobile phone.

lf a ship is built in a yard while heading north, the pales of permanent magnetism will be... red to the bow and blue to the stern. if built in the southern.

The gyro course is 332º and the gyro error is 2º High. What is the true course?. 330º. lt couId be any of the other options.

How is a ship's permanent magnetism acquired during building?. By the hammering and heating processes while heading in the same direction in the building yard. By the sun.

Variation values change for a particular place because... the magnetic pales are moving their positions in relation to the geographic pales. ionospheric changes.

The ship's magnetic compass should be adjusted following certain circumstances. From those listed, which is NOT one of those circumstances?. When a new Master joins the ship. When it appears unreliable.

From those listed, which is NOT a reason for having the standard magnetic compass high up and on the centreline in the ship?. In order to reduce the chance of damage. To keep it away from most other sources of magnetism.

The proces of turning a gravity controlled gyroscope into a compass is called... damping. ..

With reference to magnetism, soft iron... means that it can change its polarity without change of position. cannot be magnetised.

The vertical force of the earth's magnetism .... does not cause deviation of the magnetic compass. influences the variation.

Precession in relation to a free gyroscope is... the change of direction of the spin axis when a force is applied at right angles to the axis. ..

From those listed, which of the statements about the dip of a magnet is true?. At the magnetic equator, the dip is zero and the directive force greatest. At the magnetic pales.

Gaussin Error of the magnetic compass is caused by... the ship being on the same heading far a long period. external magnetic.

lf a ship has permanent magnetism with a red pole forward, the deviation caused will be... zero on north and south, west on easterly, east on westerly courses. east on westerly courses, west on easterly, zero on north and south.

Gaussin or Retentive error ... is uncertain in size and may take several hours to clear. calculated and allowed setting courses.

lf the axis of a free gyroscope in a north latitude is horizontal and pointed to the east of north of the meridian, it will... drift east and tilt up. ..

Damping in azimuth in a gyro compass produces... a settling position exactly on the meridian. an error.

The magnetic equator is... the line joining places where the dip is zero. coincident earth's equator.

Magnetic compass deviation changes with.... heading. .

A free gyroscope is said to have "three degres of freedom". From those listed, which is NOT one of these?. Latitude axis. Azimuth.

The magnetic force exerted at any point in the magnetic field varies ... inversely with the square of the distance from the magnet. ..

All gyro compasses, when on the equator, should have... no latitude error. an easterly.

From those listed, which are "soft iron" correctors?. The spheres. ..

The effect of Gaussin or Retentive error when a ship alters course is to produce a... westerly error if she swings to starboard and vice versa. vice versa.

The ship's magnetic compass should be especially checked for error following certain circumstances. From those listed, which is NOT one of those circumstances?. lf the ship has visited an area with a large value of variation. .

With reference to magnetism, hard iron... is iron which retains its magnetism when the inducing field is removed. cannot be magnetised.

Where do you find a note of the annual rate of change in the magnetic variation at a place?. In the compass rose of the charts for the area. Nautical Ephemeris.

lf a ship has permanent magnetism with a red pole to port, the deviation caused will be... zero on east and west, east on northerly, west on southerly courses. ..

The gyro course is 165º and the gyro error is 3º Low. What is the true course?. 168º. .

Gyroscopic inertia means that the spin axis of a free gyroscope ... points in the same direction in space, unless a force is applied. ..

Leading lights are in line bearing 126ºT. lf the gyro error is 2º Low, what would the gyro bearing of the leading lights be?. 124º. 2°.

Fibre-optic compasses have advantages over conventional gyro compasses. From those listed, which is NOT one of those advantages?. They are more accurate. ...

From those listed, which of the statements about the poles of a magnet is true?. The red pole will attract a blue pole and is the north seeking end. ...

The two unique properties of a free gyroscope are... precession and gyroscopic inertia. rigidity in space.

What is the main purpose of frequently recording deviation of the ship's magnetic compass in a log or compass deviation book?. To enable unforeseen changes to devaition to be quickly detected. planning of courses.

The axis of a free gyroscope is pointed at a star. From those listed, which is NOT correct?. The axis can not be disturbed from this direction while the rate of spin is maintained. axis will stay.

The point at which the helm must be applied to achieve a required course alteration is called the ...... wheel-over position. point.

The angle between the magnetic north and the true north is ...... variation. ...

How often should the auto pilot be tested in manual mode?. At least once a watch. ...

To convert a compass course to a magnetic course, it is necessary to apply..... deviation. ...

To convert a magnetic course to a true course, it is necessary to apply.... variation. ...

lf Var= 8W and Dev =4W, What is the compass error?. 12W. ...

lf the true transit bearing of two leading lights is read off the chart and the compass bearing of the two lights, when in transit, is taken, then the difference between the two bearings so obtained is the ...... compass error. ....

Magnetic compass - Var = 7W; Dev = 12E; What is the compass error?. SE. ....

lf ship's head by compass was 045 ( C). What is the true course if the variation is SW and the deviation is 9.5 W?. 030.5 ( T). ...

Magnetic Compass - lf var =6E; dev =3W, What is the compass error?. 3E. ....