Rock - Stability Test 2 Terms

The Geometric center flotation of the underwater volume of a floating vessel is the

Center of flotation

What abbreviation represents the height of the center of buoyancy

K.B

when a vessel is inclined by an external force, the

vessels center of buoyancy shifts to the center of the vessels underwater hull

at all inclinations the Metacenter(M) ism

vertically above the center of buoyancy

if your vessel will list with equal reediness to either side, the list is most likely caused by

negative GM

a tank which is not completely full or empty is called

slack

the most important figure in calculating the free surface constant of a tank carrying liquid is

Breadth

a quick and rapid motions(shift) of a vessel in a seaway is an indication of

large GM

when the height of the metacenter is less than then the height of gravity, a vessel has which type of stability

Negative

the amount of freeboard which a ship possesses has a tremendous effect on its

stability at large angels of inclination

a vessel is listed when it is

inclined due to an off-center weight

what is the stability term for the distance from the center of gravity to the metacenter M when a small angle of stability applies

metacentric Height

the differences between the height of the metacentric and the height of the center of gravity is

GM

when positive stability exsists, GZ represent the

righting Arm

the value of the maximum righting arm depends on the position of the center of buoyancy and the

vertical location of the center of gravity

if the vertical center of gravity of a ship rises. the righting arm GZ for various angles of inclination will

decrease

a moment obtained by multiplying a force(weight) by its

lever arm/ distance

at all angles of inclination, the true measure of the vessels stability is the

displacement

stability is determined principally by the location of the center of gravity and the

aft perpendicular

a slow and easy roll is a seaway is an indication of

small GM

Inclining experiment

Egg heads verify the lightship

light ship

the ship with out, fuel, cargo, ballast, crew, just the raw ship (the lightest the ship can possibly be)

M

Metacneter

G

center of gravity

B

center of buoyancy

K

Keel

Center of buoyancy

Is the geometric center of the underwater position of the hull

Internal force

Off center weight. called a list. a list is caused by offcenter weight

initial stability

the ability go a ship to right itself 10 degrees from port to starboard 10 degrees

The 3 types of stability

Based of G, B, and M. Positive stability, negative stability, and neutral stability

negative stability

center of gravity is above the metacenter

Positive stability

G is below M

neutral stability

G is the same as M

angle of loal

the ships natural angle

M

is based on the underwater form of the vessel

Longitudinal center of gravity is equal to

the trim

transverse is equal

to the list

Kg

vertical center of gravity. total vertical moments/displacement

angle of deck emersion

if you

longitudinal center of gravity equation

longitudinal moments/ displacement.

free surface effect

full tank acts as a solid, when a tank is partially filled it is called slacked

free surface is

vertical rise in the center of gravity

free surface correction

total free surface moments/ displacements