Which of the given options best describes the speed of swell waves?
Ваша відповідь правильна:
Long wavelength swell travels faster than short wavelength.
2
Which of the given options can be considered the most accurate for this statement? The position of the centre of water pressure will affect how the vessel handles when being berthed:
Ваша відповідь правильна:
A correct statement – as a berthing vessel usually has force from moving water on it.
3
Which of the given options can be considered correct for the time when a large vessel starts to feel the bottom and have increased drag?
Ваша відповідь правильна:
When the depth becomes less than six times the draught.
4
Select the option which correctly completes the following statement. “Very large waves can be destructive because they have”:
Ваша відповідь правильна:
Lots of energy.
5
Which of the given options is the most accurately completes the following statement? Water on deck of a vessel:
Ваша відповідь правильна:
Can increase top weight reducing the vessel’s stability.
6
Select from the given options one definition of heavy weather given in this module:
Ваша відповідь правильна:
When the wave height exceeds 4 metres.
7
Which of the given options best describes a cross swell in relation to sea state?
Ваша відповідь правильна:
Two swells from different directions meeting at a large angle.
8
Which of the given options is the most accurately completes the following statement? The transverse GM of the vessel:
Правильну відповідь:
Has an influence on a vessel rolling in waves.
Ваша відповідь:
Has an influence on a vessel pitching in waves.
9
Which of the given options best describes wind against tide effect?
Ваша відповідь правильна:
Wind blowing in an opposite direction to water flow.
10
Which of the given options best describes the world’s tides?
Ваша відповідь правильна:
Tides are standing waves in the oceans.
11
Which of the given options completes the following statement? A vessel stationary in a harbour on the crest of a standing wave will:
Ваша відповідь правильна:
Heave only.
12
Select the option that completes the following statement. “If the wind speed doubles”:
Ваша відповідь правильна:
The force on the vessel increases by an approximate factor of four.
13
Which of the given options is the most accurate in relation to the following statement? Very large waves can be encountered in any sea area regardless of environmental conditions:
Ваша відповідь правильна:
Not correct – as environmental conditions have to be right.
14
Select the option which correctly completes the following statement. “The Beaufort scale is used to”:
Ваша відповідь правильна:
Indicate wind strength.
15
Which of the given options best describes swell waves found at sea?
Ваша відповідь правильна:
Waves resulting from previous wind or wind in another area.
16
Which of the given options can be considered correct to complete this statement? Breaking water on the deck of a vessel:
Ваша відповідь правильна:
Can impose enormous loads on deck and deck machinery.
17
Which of the given options can be considered the best answer to a definition of the dangerous semi circle in a Tropical Revolving Storm (TRS)?
Ваша відповідь правильна:
It is the semicircle where the wind is in the same direction as the TRS movement.
18
Which of the given options best describes the direction of wind circulation in a tropical storm in the northern hemisphere?
Ваша відповідь правильна:
Anti clockwise when viewed from above.
19
Which of the given options is the most accurate in relation to the following statement? A vessel when sailing deep sea may not notice a Tsunami wave passing:
Ваша відповідь правильна:
Because of the wave characteristics.
20
Select from the given options a physical definition of a rogue wave:
Ваша відповідь правильна:
A wave that has height greater than twice the significant wave height.
21
Which of the given options can be considered a definition of temperature latitudes?
Ваша відповідь правильна:
Latitudes between 30 and 70 degrees north and south.
22
Select from the following options why very large waves build up in the sea:
Ваша відповідь правильна:
It is because all required environment factors are present.
23
Select from the given options the statement that best describes water force on a vessel:
Ваша відповідь правильна:
The force is made up form drag and skin friction.
24
Select the option which correctly completes the following statement. “Wind waves are classed as gravity waves because”:
Ваша відповідь правильна:
Gravity is the restoring force when wind stops.
25
Is the following statement true or false? “A rogue wave is usually very steep fronted”.
Ваша відповідь правильна:
True.
26
Which of the given options completes the following statement? On a large container vessel in heavy weather with waves ahead slowing down may:
Ваша відповідь правильна:
Increase the likelihood of parametric rolling.
27
Select from the given options the one which correctly completes the following statement: “Wave forces on a berthed vessel are a function of”:
Ваша відповідь правильна:
The wave height and the length of vessel.
28
Select from the given options the statement that best describes when wind force is at a maximum value on a normal vessel:
Ваша відповідь правильна:
When the wind is abeam or close to the beam.
29
Is the following statement true or false? “Waves feel the bottom when the depth of water is greater than half the wavelength of the deep water wave”.
Ваша відповідь правильна:
False.
30
Which of the given options best describes significant wave height in relation to sea waves?
Ваша відповідь правильна:
The mean height of the third largest waves.
31
Which of the given options best describes the motion of water particles in a shallow water wave?
Ваша відповідь правильна:
They move horizontally only.
32
Select the option which correctly completes the following statement. “A Beaufort wind force 10 will have a velocity of”:
Ваша відповідь правильна:
48-55 knots.
33
In temperature latitudes which pressure system is associated with strong wind? Select an option best answering the question:
Ваша відповідь правильна:
Low pressure system or cyclone.
34
Which of the given options best completes the following statement? The wavelength of a wave is the distance from:
Ваша відповідь правильна:
One wave crest to the next wave crest.
35
Which of the given options correctly describes why fin stabilisers are sometimes not as effective in heavy weather as in calmer conditions?
Ваша відповідь правильна:
If the vessels slows down lift from the fin is reduced.
36
Which of the given options is the most accurately completes the following statement? A category 5 hurricane on the Saffir-Simpson scale is:
Ваша відповідь правильна:
A severe tropical storm.
37
Which of the given options best completes the following statement? Water breaking over the bow of a large vessel with aft accommodation:
Ваша відповідь правильна:
May be causing damage not seen immediately by the crew.
38
Which of the given options is the most accurate in relation to a rogue wave?
Ваша відповідь правильна:
There will often be a large trough before the wave front.
39
Which of the given options correctly describes a vessel broaching?
Ваша відповідь правильна:
An uncontrolled manoeuvre putting the vessel beam on to waves.
40
Which of the following options best completes the following statement: “A seiche is”:
Правильну відповідь:
The oscillation of water in a harbour.
Ваша відповідь:
The oscillation of water in an ocean.
41
Select from the given options the statement that best describes how much water force there can be on a vessel compared to wind force:
Ваша відповідь правильна:
Water force can be considerably more than wind force on some vessels.
42
Which of the given options correctly describes a standing wave at sea?
Ваша відповідь правильна:
One that moves in the same direction and speed as the vessel.
43
Select the option which correctly completes the following statement. “A Beaufort wind force 10 will have associated deep water waves of average height”:
Ваша відповідь правильна:
9 metres.
44
Which of the given options can be considered a definition of fetch?
Ваша відповідь правильна:
The distance which the wind has been blowing over the sea surface.
45
Select from the given options the best definition of a vessel slamming:
Ваша відповідь правильна:
The bow re-entering the water when the vessel is pitching.
46
Is the following statement true or false? “Some areas of the world are more prone to heavy weather than others”.
Ваша відповідь правильна:
True.
47
Which of the following statements best explains why some vessels cope with heavy weather better than others?
Ваша відповідь правильна:
Heavy weather effects can be relative to the vessel.
48
Which of the given options best describes a Tsunami sea wave?
Ваша відповідь правильна:
A long wavelength wave caused by an earthquake.
49
Which of the given options is correct for the following question? If the wind force on a vessel is calculated to be 50 tonnes how many 50 tonne tugs will be required with 25 % redundancy to overcome the wind force:
Ваша відповідь правильна:
A minimum of two tugs.
50
Select the option which correctly completes the following statement. “The group wave period of a deep water wave explains why”:
Ваша відповідь правильна:
There are bigger and smaller waves in the same wave train.
51
Which of the given options best completes the following statement? A high pressure centre will:
Ваша відповідь правильна:
Temporarily depress the sea surface.
52
Select from the given options the one which best completes the following statement: “With a small under keel clearance water force can be”:
Ваша відповідь правильна:
Up to four times the deep water value.
53
Which of the given options completes the following statement? There is a risk of parametric rolling if:
Ваша відповідь правильна:
The natural roll period is twice the wave encounter period.
54
Select from the given options one of the environmental definitions of heavy weather used in this module:
Ваша відповідь правильна:
When the wind strength exceeds force 7 on the Beaufort scale.
55
Select an option that best answers the following question. In low equatorial latitudes which pressure system is associated with extremely strong wind?
Ваша відповідь правильна:
A tropical revolving storm.
56
Select FOUR of the given options which lead to a build up of very large waves:
Ваша відповідь правильна:
Very strong wind.; Wind blowing for a long time.; Wind meets opposing current.; Water depth becomes shallow for the wave length.
57
Which of the given options best describes the motion of water particles in a deep water wave?
Ваша відповідь правильна:
They have an orbital motion.
58
Which of the given options best describes synchronous rolling on a vessel?
Ваша відповідь правильна:
When the natural roll period of the vessel is the same as the wave period.
59
Which of the given options best describes why a vessel may be rolling or pitching when there is no wind?
Ваша відповідь правильна:
The vessel is suffering swell waves.
60
Which of the given options is correct for the following statement? Fetch is the important factor in allowing the formation of fully developed waves:
Ваша відповідь правильна:
The statement is only part correct as water depth is also important to wave formation.
61
Which of the given options correctly describes what happens to a vessel’s stability in heavy weather?
Ваша відповідь правильна:
Passing waves cause increases and decreases in the vessel’s transverse GM.
62
Select from the given options the statement that best describes wind on a vessel:
Ваша відповідь правильна:
The force is made up from form drag and skin friction.
63
Is the following statement true or false? “Tropical depressions can move across the equator”.
Ваша відповідь правильна:
False.
64
Which of the given options best describes the location of the world’s Tropical Revolving Storms?
Ваша відповідь правильна:
In lower latitudes across all ocean.
65
Which of the given options best describes a tidal storm surge?
Ваша відповідь правильна:
Raising or lowering of the predicted tide height.
66
Select the option which correctly completes the following statement. “The strongest winds in a temperature latitude depression often occur”:
Ваша відповідь правильна:
Behind the cold front.
67
Which of the given options best completes the following statement in relation to sea waves? The height of a wave is the distance from:
Ваша відповідь правильна:
The crest to the trough vertically.
68
Which of the given options is correct for the following statement? Slamming is an acceptable part of being in big waves:
Ваша відповідь правильна:
The statement is not correct as slamming can cause major damage.
69
Which of the given options best describes when a large vessel will start rolling in waves?
Ваша відповідь правильна:
When the encounter angle is near the beam and waves have sufficient force.
70
Which of the following options best completes the following statement: “With waves ahead a vessel with a very fine bow will”:
Ваша відповідь правильна:
Cut through the waves relatively easily.
71
Which of the given options best describes an anabatic wind?
Ваша відповідь правильна:
A wind that blows towards land from the sea.
72
Which of the given options best describes the direction of wind circulation in a tropical storm in the southern hemisphere?
Ваша відповідь правильна:
Clockwise when viewed from above.
73
Which of the given options is correct for the following statement? Storms causing heavy weather conditions occur seasonally:
Ваша відповідь правильна:
The statement is part correct – it depends upon location.
74
Which of the given options correctly describes a standing wave in harbour?
Ваша відповідь правильна:
One that has vertical movement only.
75
Indicate from given options the definition of phase wave period in relation to sea waves:
Ваша відповідь правильна:
The time for two successive crests to pass a fixed point.
76
Which of the given options is the most accurate in relation to the following statement? Synchronous rolling only occurs with beam seas:
Ваша відповідь правильна:
It is not correct as quartering seas can produce the same affect.
77
Which of the given options best completes the following statement? A low pressure centre will:
Ваша відповідь правильна:
Temporarily raise the sea surface.
78
When manoeuvring a vessel in a shallow water tidal area with tugs where should the tugs be positioned? Select the best option:
Ваша відповідь правильна:
In positions to control the water forces.
79
Which of the given options correctly describes a vessel being pooped?
Ваша відповідь правильна:
When a wave breaks on the stern of a vessel.
80
Which of the given options is correct for a local name in Australia for a Tropical Revolving Storm?