DCASE Unit 2 Ship Stability Question
and answers correctly solved
Note: - correct answers Went in after taking test and add ** for questions for
sure on the test and some notes about it, some of the ones without ** doesn't
mean it won't be on the test similar questions were asked and I don't
remember all the questions. Good luck!!
What's considered initial stability? - correct answers Tendency of a ship to
right itself within small increments of inclination 7-10 degrees
Metacenter(M) can be found through intersection of lines of force of buoyancy
at different angles within 7-10 degrees
**Center of buoyancy:** - correct answers - point where forces of buoyancy
act in vertical upward direction
- center moves to geometric center where ship inclined (geometric center of
portion of boat underwater)
**reference points for stability** - correct answers Keel, center of gravity,
center of buoyancy, metacenter
If center of buoyancy moves up, metacenter moves (up or down) - correct
answers Down (always does opposite of buoyancy)
**2 ref points for ships overall stability?** - correct answers Center of gravity
and metacenter
(Longer distance=larger righting arm)
, Use calculative draft marks for? **(Matching definition with type of draft all 4)
** - correct answers Calculate displacement (measures keel to waterline and
tell how much water is displaced)
Limiting draft marks are for what? - correct answers Limit for where to load
based off stresses on a ship, emphasis on stresses
function of loading, assigned to maintain reserve buoyancy prior to taking
damage, makes DC book true
Navigational draft marks are for what? - correct answers accounts for
everything below keel(ex. Clearance to enter a port and includes protrusions
like sonar)
Plimsoll marks are for what? - correct answers tells limiting draft mark based
on different waters you are going to
Specific for cargo boats
**What graph plots righting arm in ft vs displacement** - correct answers
Cross curves of stability
**What is intersection of two or more successive lines of buoyant force?** -
correct answers Metacenter
If I add weight above center of gravity, center of buoyancy moves? - correct
answers Moves up along with waterline
If I remove weight above COG (center of gravity), center of buoyancy moves?
- correct answers Down
and answers correctly solved
Note: - correct answers Went in after taking test and add ** for questions for
sure on the test and some notes about it, some of the ones without ** doesn't
mean it won't be on the test similar questions were asked and I don't
remember all the questions. Good luck!!
What's considered initial stability? - correct answers Tendency of a ship to
right itself within small increments of inclination 7-10 degrees
Metacenter(M) can be found through intersection of lines of force of buoyancy
at different angles within 7-10 degrees
**Center of buoyancy:** - correct answers - point where forces of buoyancy
act in vertical upward direction
- center moves to geometric center where ship inclined (geometric center of
portion of boat underwater)
**reference points for stability** - correct answers Keel, center of gravity,
center of buoyancy, metacenter
If center of buoyancy moves up, metacenter moves (up or down) - correct
answers Down (always does opposite of buoyancy)
**2 ref points for ships overall stability?** - correct answers Center of gravity
and metacenter
(Longer distance=larger righting arm)
, Use calculative draft marks for? **(Matching definition with type of draft all 4)
** - correct answers Calculate displacement (measures keel to waterline and
tell how much water is displaced)
Limiting draft marks are for what? - correct answers Limit for where to load
based off stresses on a ship, emphasis on stresses
function of loading, assigned to maintain reserve buoyancy prior to taking
damage, makes DC book true
Navigational draft marks are for what? - correct answers accounts for
everything below keel(ex. Clearance to enter a port and includes protrusions
like sonar)
Plimsoll marks are for what? - correct answers tells limiting draft mark based
on different waters you are going to
Specific for cargo boats
**What graph plots righting arm in ft vs displacement** - correct answers
Cross curves of stability
**What is intersection of two or more successive lines of buoyant force?** -
correct answers Metacenter
If I add weight above center of gravity, center of buoyancy moves? - correct
answers Moves up along with waterline
If I remove weight above COG (center of gravity), center of buoyancy moves?
- correct answers Down
