問題一覧
1
How would you categorize the advantage of the magnetic compass aboard vessels?
It is reliable due to its essential simplicity
2
Which of the following is used to remove the deviation on the intercardinal compass heading?
Soft iron sphere on the side of the compass
3
The magnetic compass magnets are acted on by the horizontal component of the Earths total magnetic force. Where can you experience this magnetic force is GREATEST?
magnetic equator
4
What is the principal purpose of magnetic compass adjustment?
to reduce the deviation as much as possible
5
What information does the outer ring of a compass rose on a nautical chart provide?
True direction
6
The range course of the two beacon is 157 degrees. The magnetic compass deviation is 3 degrees East. The variation is 6 degrees West. What course would you steer per standard compass to make good the true course of the beacon in range?
160° PSC
7
You observe the bearing of lighthouse 118° by standard compass. What is the true bearing of the light house if variation is 3°W and the deviation is 2°E?
117° T
8
What is the angular difference between magnetic heading and compass heading?
Deviation
9
What Is the fundamental characteristic of gyro compass as it's tendency as revolving body to uphold its plane of rotation
Gyroscopic inertia
10
What is the line that pins to align the compass with the vessel heading?
Lubber line
11
While underway how often you should determine the error of the standard magnetic compass?
Atleast once every watch
12
How does the north seeking action of the gyrocompass produce?
It is produce by mutual action among the characteristic of the gyroscope, rotation of the earth and gravity
13
You are on course 125° PSC. The wind is southwest causing 3° leeway, variation is 6°E, deviation is 2°W and the gyro error is 1°W. What is your course made good?
121° T
14
What does the agonic line on an isomagnetic chart indicates?
Points where there is no variation
15
Your ship is steaming at night with the gyropilot engaged when you notice that the vessels course is slowly changing to the right. What action should you take FIRST?
Switch to hand steering
16
You just completed the magnetic compass adjustment on magnetic east and magnetic south. The vessel is now steady on magnetic west but the compass read 266°. What action should be taken?
Adjust the compass with the fore-and-aft magnets until the compass read 268°
17
What happens to the compass card in a magnetic compass when a vessel changes course to starboard?
Remained aligned with compass north
18
Which is NOT true about gyro compass compare to magnetic compass?
It is hampered by external magnetic fields
19
What magnetic compass correctors you will use for correcting both permanent and induced effects of magnetism?
Heeling Magnets
20
Where is the greatest directive force exerted on the magnetic compass?
When the vessel is near the magnetic equator
21
If your ship is proceeding toward the magnetic equator, what will happen to the uncorrected deviation due to permanent magnetism?
The uncorrected deviation will decrease
22
In gyro compass principle, what is the small torque about the vertical axis which produces effect of precession about the horizontal referred to?
ballistic tilt
23
You desire to make good course 152°. The magnetic compass deviation is 4°E, variation 5°E and the gyro error is 3°E. A southwesterly wind produces 4° leeway. What course would you steer per standard compass to make good the true course?
147° PSC
24
What should be done when a magnetic compass is not in use for a prolonged period of time?
it must be shielded from direct sunlight
25
What is the gyro compass error resulting from your vessel movement other than east-west direction?
Speed error
26
What are the purpose of magnets placed in the horizontal trays of the compass binnacle
To compensate for the permanent magnetism of the vessel
27
What is the principal purpose of magnetic compass adjustment?
To reduce deviation as much as possible
28
What course you should steer PSC to make good the true course 152°, if the magnetic compass deviation is 4°E and variation is 5°E?
142° PSC
29
What is the resultant motion perpendicular to the direction of the force when applied to change the alignment of the spin axis?
Precession
30
What is the purpose of the soft quadrantal spheres mounted on arms of the binnacle?
It is to compensate induced magnetism in the horizontal soft iron
31
What are the broken series components of the total magnetic effects which cause deviation of the vessel magnetic compass?
Coefficients
32
On the chart it indicate the variation was 3°45' W in 2017 and the annual change is decreasing 6'. What variation you should apply if you are to use the chart in 2020?
3°27' W
33
The ballistic tilt causes the axle to wander slightly after an alternation if course and/or speed because of the inclination of the axle. What is this wandering is refered to?
ballistic tilt effect
34
If you are steering on course 130 degrees PSC, what be your course made good if the compass deviation is 4 degrees West and variation is 3 degrees East and with a SWxS wind causing 2 degrees leeway?
127°T
35
What is the vertical component of the oscillation made by the elliptical path traced out by each end of a liquid gravity controlled gyro?
azimuth oscillation
36
If your ship is proceeding towards the magnetic equator, what will happen to the uncorrected deviation due to permanent magnetism?
The deviation will decrease
37
When adjusting a magnetic compass for error, at what instance a deviation table should be made?
After adjusting the fore-and-aft and athwarships permanent magnets
38
When using a gyro compass, which statement is TRUE when applying the gyro compass error?
The amount of the error and sign will be generally the same in all heading or bearings
39
According to the present theory, how would the magnetic field around a current carrying wire and the magnetism of permanent magnet are created?
By moving electric charges
40
A vessel is heading magnetic northwest and its magnetic compass reads a heading of 318 deg. What action should be taken to remove this error during compass adjustment?
By moving the quadrantal spheres in
41
What causes vessel's permanent magnetism?
It caused by the Earth's magnetic field affecting the ship's hard iron during construction
42
What will be the deviation if the magnetic heading is greater than the compass heading?
Easterly
43
The basic principle of a magnetic is, like poles repel and unlike poles attract. How would you describe the force between the magnetic poles?
Being directly proportion to the strength of the pole
44
The spin axis of a gyroscope tends to remain fixed in space in the direction in which it is started. How does this gyroscope become north seeking so that it can be used as a compass?
By mechanically or electrically applying forces to precess the gyroscope
45
Which is TRUE about the deviation of a magnetic compass onboard ship?
It is a magnetic influence inherent to that particular vessel
46
You are on course 027°T and observed a relative bearing of the lighthouse to be 220°. What is the true bearing of the lighthouse?
247°
47
From your true course how can you find the magnetic course?
By applying variation