問題一覧
1
Based on what you know, what will happen to the compass card of a magnetic compass when a vessel changes course to starboard?
It will remain alignment with compass north
2
The vertical component of the Earth magnetic field causes induced magnetism in vertical soft iron and this changes with latitude. How could you correct this coefficient of the deviation?
It could be corrected by the Flinders bar
3
What is the angular difference between true north and the magnetic meridian?
Variation
4
What is the true bearing of the object if the compass bearing is 055° with variation of 4° W, and the deviation of 1° E?
052°T
5
Which of the following is used to compensate for induced magnetism in the horizontal soft iron of a vessel?
Iron sphere mounted on a binnacle
6
How does the north seeking action of the gyro compass is produced?
It is produced by the mutual action among the characteristic of the gyroscope rotation of the earth and gravity
7
What is the system that keep the compass card level when ship heels and pitches?
Gimbal system
8
Which is TRUE when a gyroscope is placed at the equator with it's spin axis pointing E-W as the earth turn on its own axis?
The gyroscopic inertia will tend to keep the plane of rotation constant
9
What will happen if a gyroscope is placed at the equator with the spin axis pointing E-W, as the earth turn on its own axis?
Gyro inertia will tend to keep the plane of rotation constant
10
How would you identify the error of your magnetic compass if it has no deviation?
The compass error is equal to variation
11
The ship's total magnetic force is split into three components, Which is not a component Force of ship total magnetic force?
directive force component
12
What is known as the apparent movement of a gyro axis is analogous to the change in azimuth of a fixed star?
change of drift
13
Which of the following is a cause of compass variation?
Magnetism from the earth magnetic field
14
Which of the following nautical table published for the rapid solution of solving plain sailing, also covers to solve distances up to 600 miles and among others such as amplitude?
Traverse table
15
What is the reaction of a gyro compass to an applied force?
Precession
16
How does the directive force of gyro compass work?
It decreases with latitude, being maximum at the geographic equator
17
What factor produces oscillations in the directive force of a gyro which creates temporary dislocation in it's direction until it is oriented?
Change in the course and speed
18
What is the functionality of a Flinders bar on a magnetic compass?
It is to compensate the induced magnetism in vertical soft iron
19
From point A to point B the true course is 215° the gyro error is 2° west. A North wind cause 3° leeway. What course would you steer per gyro compass to make good the true course?
220° PGC
20
What is the primary reason for a compass deviation vary in every change course of a vessel?
The deviation will vary with direction
21
A vessel is heading magnetic northwest and it's magnetic compass indicate a heading of 312°. The quadrantal spheres are arrange athwarships. What action should be taken to remove this error during compass adjustment?
If the quadrantal spheres are all the way out, replace them with smaller sphere
22
Ballistic damping error is a temporary oscillation introduced by changes in course or speed. How this error affects the vessel's heading?
This causes a torquing if the spin axis and subsequent error in the compass reading
23
A gyro- compass is a type of nonmagnetic compass which automatically find geographical direction. How does it work?
It depends upon on four natural phenomena gyroscopic inertia, precession, Earth rotation and gravity
24
What keep the phantom element of a gyro compass alignment with the sensitive element?
By the azimuth motor
25
What is the cause of variation which affects the directive force of a magnetic compass of a ship?
The magnetic force from the earth magnetic field
26
The plotted course between two points is 090T l. What course will you steer the magnetic compass if the variation in the locality is 12E, and the magnetic compass deviation is 5E?
You should steer the course to 073 PSC
27
What is the direction in which a North Pole would be urged in that field of the magnet away from the red towards the blue pole?
direction of the field
28
What would be the variation in year 2008, if the variation was 7°55'W in 1979 and decreasing 4' annually?
5°59' W
29
What does the lubber line of a magnetic compass indicates?
It is the indicates of the vessel's heading
30
Which statement statement is correct regarding magnetic compass deviation?
It is the divergence between N-S axis of the compass card and the magnetic meridian
31
What should you apply when changing from a compass course to a true course?
Variation and deviation
32
To determine your true course what should you apply to the compass course?
variation and deviation
33
Which statement is true about the directive force of a gyrocompass?
It decrease with latitude and maximum at geographical equator
34
Where is the point where the magnetic field is vertical
Magnetic pole
35
What is the caused of variation of a magnetic compass?
magnetism from the earth magnetic field
36
How would you categorize the advantage of the magnetic compass aboard vessels?
It is reliable due to its essential simplicity
37
What is the most accurate method of determining gyrocompass error while your vessel is underway?
Comparing the azimuth of the celestial body with the computed azimuth of celestial body
38
What do you compensate when you place a single vertical magnet underneath the compass binnacle?
deviation caused by the vessel inclination from the vertical
39
When shutting down a gyro compass, you do all of the following EXCEPT:
Balance rotor
40
Where does the compass card attached in the master gyro compass?
sensitive element
41
Is a magnetic theory that believes the atoms within the molecules are themselves dipoles, meaning having two magnetic poles.
Bi-polar theory
42
Which of the following statement about the Flinders bar on a magnetic compass is TRUE?
It is to compensates for the error caused by the vertical component of the Earth's magnetic field
43
What is the gyrocompass error causes by ship's forward motion along the tracks?
Speed error
44
How does the indications of the master gyrocompass sent to remote repeaters?
It is sent by transmitter
45
The wind is SWxS causing 2 degrees leeway. The variation is 3 degrees East, the deviation is 4 degrees West and the gyro error is 1 degree West. What will be your course made good if you are steering on course 130 degrees PGC?
127°T
46
While in an open sea what is the most accurate method of determining the gyrocompass error?
Compare the gyro azimuth of a celestial body with the computed azimuth of the body
47
What is the term use to describe the movement of the axle of a gyro under the influence of an external force?
Precession
48
If a magnetic compass is not affected by any magnetic field other than the earths, which statement is TRUE?
Compass error and variation are equal
49
You are proceeding up a channel at night marked by a range light bearing 135°. You steady up your course at 130° with the range dead ahead. What does this indicates?
Your compass has an easterly error