navigational problems

7/29/2019 navigational problems

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1. The maximum length allowed betweenmain and traverse bulkheads on a

vessel as referred to as:A. Permissible length

B. Floodable length

C. Factor of Subdivision

D. Compartment standard


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2. The term "scantlings " refers to the:

A. draft of a vesselB. measurements of structural

members

C. requirements for ship's gearD. placement of a vessel's loadline


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3. A welded joint's effectiveness isconsidered:

A. 48%

B. 90%

C. 100%D. 121%


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4. The smallest size of flaw that can bedetected on a radiograph examination

of a weld will be indicated by the:A. film speed

B. penetrometer

C. exposure reading

D. time of exposure


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5. While in drydock your vessel will bebelt-gauged. This process involves:

A. Measuring the thickness of the tailshaft liner.

B. Taking the vessel's offsets to check

for hull deformationC. Testing and examining the anchor

cables for defective links.

D. Drilling or sonic-testing the hull todetermine the plate thickness


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6. A large basin cut into the shore, closed off

by a caisson, and used for drydocking ofships is known as a:

A. Slip way

B. Graving dockC. Ground warp

D. Caisson Dock

- SPACE IN SHIP BUILDING YARD.

- A MANILA & WIRE ROPE/IN

FRENCH RIGGED TRAWL NET- CHAMBER FOR WORKING UNDER

WATER


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7. Which statement about a vessel's stabilitywhile dry-docking is true?A. Every ton of weight bearing on theblocks acts as if a ton of weight wasremoved at keel level.B. When the ship touches the blocks, the

beam for stability purposes increases tothe beam of the dry dock.C. The stability of the vessel increases asa dock is pumped out due to the support

of the keel blocks.D. As the dock begins to support theweight of the vessel, stabilitycalculations are based on the ship and

dock as a single unit.


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8. The purpose of inclining experiment ona vessel is to determine:

A. Lightweight center of gravity

location

B. The position of the center of

buoyancy

C. The position of the metacenter

D. The maximum loadline


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9. When making a turn on most merchantships, the vessel will heel outwards if:

A. A vessel has very little draftB. G is above the center of lateral

resistance

C. G is below the center of lateralresistance

D. The vessel is deeply laden


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10. Forces within a vessel have caused adifference between the starboard and

port drafts. This difference is:A. list

B. heel

C. trim

D. floatation


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11. If the cause of severe list or trim isoff-center ballast, counterflooding into

empty tanks will:A. increase the righting moment

B. increase the righting arm

C. increase list or trim

D. decrease list or trim


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12. If the cause of a sudden severe list ortrim is negative initial stability,

counterflooding into empty tanksmay:

A. increase the righting moment

B. cause an increase in the rightingarm

C. bring the unit to an upright

equilibrium position

D. cause the unit to flop to a greater

angle


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13. GM cannot be used as an indicator ofstability at all angles of inclination

because:A. M is not fixed at large angles

B. There is no M at large angles

C. G is not fixed at large angles

D. There is no G at large angles

14 O l f 9 000 di l


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14. On a vessel of 9,000 tons displacement,there are two slack deep tanks of palm oil(S.G. 0.86). Each tank is 40' long and 30'

wide. What is the reduction in metacentricheight due to free surface with the vesselin sea water (S.G. 1.025)?

A. 0.24 ft

B. 0.48 ft

C. 0.57 foot

D. 0.74 ft

FSC = r l b3

420 = (.839)(40)(30)3

420 (9,000)

= .2397

x 2

.4794

r = spec. grav. of liquid in tk.spec. grav. where vsl float

= 0.86

1.025

= 0.839


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15. What is the principal danger from theliquid in a half-full tank on board a

vessel?A. Corrosion from the shifting liquid

B. Rupturing of the bulkhead from the

shifting liquidC. Loss of stability due to free

surface effect

D. Holing of the tank bottom from theweight of the shifting liquid


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16. A ship is lying at the mouth of the river inwater density 1024 kgs/m3 and thedisplacement is 12,000 tonnes. The ship is

to proceed up river and to berth in dockwater of density 1008kgs/m3 with the samedraft as at present. Find the amount of

ballast to be discharge:A, 195.7 T

B. 193.0 T

C. 187.5 T

D. 189.6 T

N DISPL. = N DENS.O DISPL O DENSN DISPL = O DISPL X N DENS

O DENS= 12,000 X 1008

1024

= 11,812.5

() 12,000

= 187.5


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17. Relative density of a substance is thenumber of times that any volume of

the substance is heavier than an equalvolume of pure fresh water at atemperature of:

A. 0 CB. 4 C

C. 0 F

D. 4 F


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18. In accordance with the internationalload line convention (1966), whichbecame effective in July 1968, loadlineswere established for all new vessels ofwhat gross tonnage?

A. 150 gross tons or over if they

engaged in foreign voyageB. 300 gross tons or over if they

engaged in foreign voyage

C. 400 gross tons or over if theyengaged in foreign voyage

D. Less than 400 G.T


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19. It means a special load line assigned toships complying with certain conditions

related to their construction set out inthe international convention on loadlines and used when the cargo complies

with the stowage and securingconditions of this code.

A. Summer load line

B. Timber load lineC. Winter North Atlantic load line

D. Tropical fresh load line


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20. Cargo that is highly susceptible todamage by tainting from odorous cargo

is called _____.

A. clean cargo

B. delicate cargo

C. dry cargo

D. immune cargo


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21. Cargo that gives off fumes that maycontaminate other cargo is known asa ( n ) _________.

A. delicate cargo

B. dirty cargo

C. toxic cargo

D. odorous cargo


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22. The internal volume of a cargo holdmeasured from the inside faces of the

cargo battens; and lower side of thedeck beams, and the top of the tanktop ceiling is known as the:

A. gross tonnageB. deadweight space

C. bale cubic

D. stowage area


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23. Which term describes goods having astowage factor below 40?

A. deadweight cargo

B. full and down cargo

C. heavy-lift cargo

D. measurement cargo


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24. If you want to lift small particles,which of the following would you use?

A. Pallet

B. Cargo hook

C. SlingD. Cargo net


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25. When two-leg sling attached to onehoist line is used to lift a load, a sling of

40 ft in length is better than one of 30 ftbecause the:

A. tension in the sling legs is less

B. load can be lifted higher

C. sling will be easier to attach

D. sling will be easier to remove


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26. A periodic thorough examination ofthe cargo gear proves satisfactory.

What percentage of the total gearmust be dismantled to determineactual internal condition?

A. noneB. 10%

C. 25%

D. 100%


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27. All wire rope used in shipboard cargogear must be identified and described

in a certificate. The certificate shallcertify all of the following except?

A. date of the test

B. load at which a test sample broke

C. name of the vessel

D. number of strands and of wires ineach strand


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28. What is required to be stenciled at theheel of a cargo boom?

A. maximum angle of elevationpermitted

B. date of the last quadrennial test

C. safe working load

D. maximum load when doubled up


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29. Which of the following statements about thecarriage of solid hazardous materials in bulk istrue?

A. A special permit issued by the coast guard isrequired before the cargo is loaded.

B. The loading of cargo must be conductedunder the direction and observation of a personemployed or assigned for that purpose.

C. A certificate issued y ABS will be acceptedas evidence that the vessel complies with allapplicable loading regulations.

D. The shipping papers must indicate theprimary hazardous characteristics or property ofthe material.


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30. It means that a piping on ventingsystem, for example, is in no way

connected to another system and thatthere are no provisions available forthe potential connection to other

system.A. segregated

B. self-contained

C. independentD. separate


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31. This is a cargo ship constructed oradapted and used for the carriage in

bulk of any liquid product.A. Product tanker

B. Crude carrier

C. Chemical tanker

D. LPG tanker


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32. A tank vessel propelled by power is a

A. tank ship

B. tank vessel

C. tank barge

D. any of the above


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33. A flammable liquid with a reid vaporpressure of 8 1/2 psi or less and a

flash point of 80 F and below is grade.A. B

B. C

C. A

D. All of the above


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34. The lowest temperature at which aliquid will give off vapors that will

burn when ignited but will stopburning once the source of ignition isremoved, is called its:

A. flash pointB. anti-ignition temperature

C. fire point

D. lower explosive limit


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35. The minimum concentration of avapor in air that can form an explosive

mixture is referred to as the:A. auto- ignition temperature

B. flash point

C. lower explosive limit

D. fire point


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36. The vapor pressure of a gas is apressure necessary to keep it in a(n):

A. soluble state

B. solid state

C. liquefied state

D. inert state


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37. Coast guard regulations that electricand electro hydraulic steering gear

motors shall be.A. served by two electric power feeder-circuits

B. provided with a motor-running overcurrent protection device

C. protected by a circuit breaker and a

thermal overload deviceD. served by a single two-conductorcable


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38. The warning sign used on tankvessels when moored or anchored

and transferring a petroleum cargosays:

A. "danger, do not approach, do not

board"B. "warning, no smoking, no open

lights, no visitors

C. " dangerous cargo"D. all of the above


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39. Smoking is not permitted on theweather decks of tank vessels:

A. a except when sand pails areprovided and are filled

B. except when water is being used to

cool the decksC. when loading cargo through open

hatches

D. under any circumstances unless

the vessel is gas free and is notalongside


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40. The minimum protective clothingoutfit to wear when taking cargo

samples of a hazardous cargo on atank ship includes:

A. hood or hard hat

B. face mask or gogglesC. boots

D. chemical resistant gloves


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41. Stop loading grade A, B or C cargoimmediately if:

A. another ship or tug comes alongsidenear the area of the transfer

B. a fire starts on the dock on your

vessel or on nearby ship

C. any electrical storm approaches

D. any of the above happens


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42. If an oil hose leaks a very smallamount through its fabric:

A. reduce pressure in the hose andcontinue pumping

B. "quick patch" the leak and use a

drip pan if the leak is smallC. clamp the leak using two hoseclamps and a section of inner tube

and equivalentD. shut down and replace the hose


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43. It means filling the ullage space with a

moisture free gas ( dew point


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44. Pollution regulations require thateach scupper in an enclosed deck

area have a:A. wooden plug

B. soft rubber plug

C. mechanical means of closing

D. none of the above


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45. How much space must you leave in atopped off tank for liquid expansion?

A. No space is permitted: the tank mustbe pressed up to reduce free surface

effect

B. Generally 1% to 3% of the tank

volume

C. The amount specified on the

certificate of inspection

D. None of the above


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46. The most likely time for oil pollutionwhen bunkering is when:

A. final topping off occursB. first starting to receive fuel

C. hoses are being blown down

D. hoses are disconnected and beingcapped


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47. These are used as intermediates forthe production of chemicals, as

solvents and for gasoline blending.Examples of these products arebenzene , and xylene.

A. essential oilsB. vegetable oils

C. aromatics

D. animal oil


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48. Under the IMDG code, all hazardouscargoes are assigned to, a category

representing their major hazard. Thesecategories are assigned a number andare called:

A. classB. group

C. file

D. section


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49. Corrosive liquids and acids shouldhave what kind of level?

A. skull and crossbonesB. yellow

C. red

D. white


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50. Which of the following is not requiredas special safety equipment on a tank

ship carrying hazardous cargoes inbulk?

A. shower and eyewash fountain

B. equipment to lift an injured personfrom a pump room

C. two portable vapor detectors suitable

for the cargoes carriedD. a safe locker adjacent to the safety

emergency shutdown station

51 I i th l d t th d t


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51. In using the load on top method tocontrol pollution, what action should you

take after transferring all dirty ballast tothe slop tank?

A. The clean tanks should be ballasted

B. The slops should be allowed time tosettle

C. Chemicals should be added to

emulsify the oilD. The dirty ballast tank is crude oil

washed


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52. Marpol 73/78 states that discharge ofpetroleum products in any form is

pollution. Which of the following isnot, even if discharge to the sea?

A. grease

B. crude oilC. used cooking oil

D. sludge from ship's oil tanks


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53. Regulations covering the varioussources of ship-generated pollution

are contained in the:A. articles of the 1973 marpol

convention

B. five annexes to the marpolconvention

C. article 2 of the 1973 convention

D. protocol of 1978 relating to theinternational convention

54 Which of the following statements about


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54. Which of the following statements abouttank cleaning is/are true?

I. Products which are volatile and

vaporize without traces frequently

needs cold washing

II.Vegetable oils and animal oils of non-drying type should preferably be pre-

washed directly with hot water (

89 C )A. I only

B. Neither I nor II

C. Both I and II

55 You are approaching the pilot station


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55. You are approaching the pilot stationwith the wind fine on the starboard bow

and making about 3 kts. You can help tocalm the seas by taking what action justbefore the pilot boat comes along on theport side?

A. backing full

B. stepping the engine

C. giving the right full rudderD. a short burst of ahead full with left

full rudder


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56. When the pilot is embarked, he:

A. is a specialist hire to give

navigational advice

B. is solely responsible for the safe

navigation of the vessel

C. relieves the master of his duties

D. relieves the officer of the watch


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57. Before a master relieves a pilot of theconn the:

A. Master must first request the pilot totake corrective action

B. Master should foresee a danger if the

vessel remains on the present course

C. Master should agree to sign a release

of liability form

D. Vessel must be in extremis

58 F th d t t h ti ti


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58. For the deepest water when negotiatinga bend in a river, you should always

navigate your vessel:A. toward the inside bend of the river

B. toward the outside bend of the river

C. toward the center of the river justbefore the bend, then change course

for the river's center after the bend

D. toward inside or outside bend of the

river


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59. A condition where two currents meetat a down stream end of a middle bar

can be determined by a:A. small whirlpool

B. smooth patch of water

C. v-shaped ripple with the point of

the V pointing downstream

D. v-shaped ripple with the point of

the V pointing upstream


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60. The most favorable condition toencounter when you dock your vessel

is when the wind and current are:A. crossing your course in the same

direction

B. crossing your course in the

opposite direction

C. parallel to the pier from ahead

D. setting you on the pier


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61. A common occurrence when a vesselis running into shallow water is that:

A. the wake is less pronouncedB. the vessel is more responsive to

the rudder

C. "squat" will cause a decrease in

bottom clearance and an increase

in draft

D. all of the above

62 T f l h l th t


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62. To safely anchor a vessel, there mustbe sufficient "scope" in the anchor

cable. Scope is the ratio of:A. weight of cable to weight of vessel

B. weight of cable to weight of anchor

C. length of anchor to depth of waterD. length of cable to depth of water

63 When anchoring it is a common rule


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63. When anchoring, it is a common ruleof thumb to use a length of chain:

A. five to seven times the depth ofwater

B. seven to ten times the depth of

water

C. twice the depth of water

D. twice the depth of water plus the

range of tide

64 You are proceeding down a channel and lose the


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64. You are proceeding down a channel and lose theengine (s). You must use the anchors to stop theship. Which statement is true?

A. Pay out all the cable before setting up on

the brake to insure the anchors dig in and hold.

B. For a mud, mud and clay, or sandy bottom pay

out a scope of 5 to 7 times the depth beforesetting up on the brake.

C. Use one or both anchors with a scope of twicethe depth before setting the brake.

D. Drop the anchor to shore stay and hold thatscope.

65 Wh tt ti t f h


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65. When attempting to free an anchorjammed in the hawse pipe, the simplest

method of freeing it may be:A. a simple kick, such as starting the

windlass at full power

B. rigging a bull rope to pull it outC. to grease the hawse pipe

D. to try it loose with a short piece of

pipe

66 When anchoring in calm water it is best


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66. When anchoring in calm water, it is bestto:

A. maintain slight headway when lettinggo the anchor

B. wait until the vessel is dead in the

water before letting go the anchorC. have slight sternway on the vessel

while letting go the anchor

D. let the anchor go from the stern withthe anchor cable leading from the

bow

67 Y di i h th


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67. You are proceeding in heavy weatherand you have your bow meeting the

seas. To prevent pounding, youshould:

A. change course, in order to take the

seas at an 85 angle from the bowB. decrease speed

C. increase speed

D. secure all loose gear

68 In heavy weather you notice buckling in


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68. In heavy weather, you notice buckling inthe midships deck plating of your

vessel. To relieve the strain , you could:A. pump fuel oil from midships to the

ends of the vessel

B. reduce speedC. take a course which most eases the

vessel

D. all of the above


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69. The period of roll is the time differencebetween:

A. zero inclination to full inclination on

one side

B. full inclination on one side to full

inclination on the other side

C. full inclination on one side to the

next full inclination on the same sideD. zero inclination to the next zero

inclination

70 Whi h h t i ti i di d t


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70. Which characteristic is a disadvantageof a controllable-pitch propeller as

compared to a fixed-pitch propeller?A. slightly higher fuel consumption

B. lack of directional control when

backingC. inefficient at shaft rpm

D. some usual handling characteristics

71 You are on a single screw left handed


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71. You are on a single-screw left handedpropeller vessel. When you have full

sternway with left full rudder, youshould expect the stern to swing:

A. quickly to starboard, then slowly to

portB. slowly to port, then quickly to

starboard

C. to portD. to starboard

2 Whi h f i i h d


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72. Which type of ice is a hazard tonavigation?

A. ice rind

B. pancake ice

C. frazil ice

D. growlers


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73. The proximity of pack ice may beindicated by

A. changes in sea water salinity

B. glare on clouds on the horizon

C. changes in air temperature

D. icebergs


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74. Ice concentration is measured inOKTA's. What percentage of the sea

surface is ice- covered with 4 OKTA'sconcentration?

A. 25%

B. 40%

C. 50%

D. 67%

75 How should you warm-up a diesel


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75. How should you warm-up a dieselengine that has not been run for

sometime?A. run it at minimum speed for a

period of time

B. run it at half speed for a period oftime

C. bring it to top speed immediately

D. inject either into the air intake

76 Th th diti hi h


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76. The three conditions which causeengine shut down are over speed, low

lube oil pressure and:A. high lube oil pressure

B. high jacket water pressure

C. high jacket water temperature

D. low jacket water pressure

77 Which of the following is an advantage of


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77. Which of the following is an advantage ofa steam turbine over a diesel for the main

propulsion?A. faster response form ahead to astern

B. less fuel consumption

C. cheaper initial installation costD. less weight per unit of horsepower


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78. The brickwork surrounding thefirebox of a boiler is known as:

A. Refractory

B. The screen wall

C. The water wall

D. Fire plate


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79. In a water tube marine boiler, whatprotects the super heater tubes from

the fire of combustion?A. water-wall tubes

B. down comers

C. screen tubes

D. water drums


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80. The pillar shape that gives thegreatest strength for the least weight

is the:A. Octagonal pillar

B. "H" beam pillar

C. "I" beam pillar

D. Circular type pillar

81 Th f ldi l d i


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81. The type of welding employed inshipyards is primarily:

A. brazing

B. electric arc

C. pressure welding

D. thermite welding

82 Which weld fault can only be detected


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82. Which weld fault can only be detectedby a method that examines the

internal structure of a weld?A. Undercut

B. Lack of reinforcement

C. Overlap

D. Lack of penetration

83 Which type of weld testing can be


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83. Which type of weld testing can beused to detect the internal flaws?

A. RadiographicB. Magnetic particles

C. Dye penetrant

D. Chemical reaction

84. What is not an item that requires the


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84. What is not an item that requires thevessel to be dry-docked?

A. Inspection of tail shaft linerB. Repacking and grinding of skin valves

C. Verification of loadline measurements

D. Belt gauging

85 Wale shores would be used when


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85. Wale shores would be used whendrydocking a vessel with:

A. Tumble homeB. Excessive dead rise

C. Excessive trim

D. A list

86 Aboard a vessel dividing the sum of


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86. Aboard a vessel, dividing the sum ofthe traverse moments by the total

weight yields the vessel's:A. Vertical moments

B. Transverse position of the center of

gravityC. Inclining moments

D. Righting moments

KG = TOTAL MOMENTS

TOTAL WEIGHT

87 A virtual rise in the center of gravity


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87. A virtual rise in the center of gravitymay be caused by:

A. Filling a partially filled tankB. Using an onboard crane to lift a

freely swinging heavy object

C. Emptying a partially filled tank

D. Transferring ballast from the

forepeak to the after peak

88. Which of the following is the correct definition of


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transverse metacenter?

A. The distance between the actual center

of gravity and the maximum center of

gravity that will still allow a positive

stability.

B. The point to which G may rise and still

permit the vessel to possess positive

stability.

C. The sum of the center of buoyancy andthe center of gravity

D. The transverse shift of the center of

buoyancy as a vessel rolls.

89. A vessel continually lists to one side


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89. A vessel continually lists to one sideand has a normal rolling period. Whichof the following statements is true?

A. A vessel has negative GM

B. The center of gravity is on the

centerline

C. The list can be corrected by

reducing KM

D. The vessel has asymmetrical weightdistribution

90. During cargo operations, your vessel


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g g p , yhas developed a list due to the center

of gravity rising above the transversemetacenter. To correct the list, youshould:

A. shift weight to the high side

B. shift weight to the centerline

C. add weights in the lower holds on

double bottomsD. remove weights from the lower

holds or double bottoms

91. The angle of maximum stability


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g ycorresponds approximately to the

angle of:A. deck edge immersion

B. the load line

C. downfloodingD. loll

92. Your vessel has a displacement of


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p10,000 tons. You have on board a

slack tank measuring 50' long by 60'wide by 5' deep. (S.G. 0.65) What isthe reduction in metacentric heightdue to free surface?

A. 1.54 ft

B. 1.59 ft

C. 1.61 ftD. 1.71 ft

FSC = r l b3

420 = (.63)(50)(60)3

420 (10,000)

= 1.62

r= .651.025

r = .63

93. On a vessel of 34,000 tons displacement, a tank80' long 60' wide and 30' deep is half filled with


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80 long 60 wide and 30 deep is half filled withdock water (S.G. 1.015). While the vessel isfloating in saltwater (S.G. 1.025). What is the freesurface constant of this tank.

A. 42,213

B. 40,100

C. 40,741

D. 41,500

FSK = r l b3

420

= (.99024)(80)(60)3

420

= 40,741

r = spec. grav. of liquid in tk.

spec. grav. where vsl float= 1.015

1.025

= 0.99024

94. The effects of free surface on a


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vessel's initial stability do not depend

upon the:A. volume of displacement

B. dimension of the surface of the

liquidC. amount of liquid in the tanks

D. specific gravity of the liquid in the

tank

95. A box shaped vessel draws 7.5 m in


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95. A box shaped vessel draws 7.5 m indock water of density 1,006 kgs/m3.

Find the draft in salt water of density1,025 kgs/m3.

A. 7.678m

B. 7.939mC. 7.49 m

D. 7.361 m

N DR = O DENSO DR N DENSN DR = O DR X O DENS

N DENS= 7.5 X 1,006

1,025

= 7.3609 m

96. Loadline markings indicate the drafts


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gat which, for various conditions and

types or classes of vessels, there willstill be left a sufficient percentage of__________to ensure the vessel'ssafety.

A. transverse stability

B. reserve buoyancy

C. intact buoyancyD. longitudinal stability

97. In accordance with the international


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9 acco da ce t t e te at o aload convention (1966) which became

effective in July 1968, loadlines wereestablished for all new vessels ofwhat length?

A. 150 ft or more in lengthB. 100 ft or more in length

C. 79 ft or more in length

D. 200 ft or more in length

98. When referring to dry bulk cargoes, theterm " flow state "


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term flow state .

A. Designates the state of a commodity

when the ship is heeled past the angle ofrepose

B. Relates to the suitability of loading a

cargo by flowing down inclined chutes.C. Refers to the saturation of a dry bulkproduct with water to the point where it

acts as a liquid.D. Relates to the minimum granule size ofa particular product where it will flow like

a liquid at an angle of 30

99. A hygroscopic cargo is defined as a


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cargo ___________.

A. capable of absorbing moisture inthe form of gas

B. capable of giving off moisture in

the form of a liquidC. that is shipped in a liquid state

D. that will ignite in contact with water

100. Which is characteristics of a


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"special cargo"?

A. The cargo gives off toxic gasseswhen heated

B. Periodic inspection is required

while in transit to prevent spoilageC. It is high value or easily pilferable

D. It must be stowed on deck

navigational problems

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