Although KG for a MODU in lightweight is relatively high, the vessel is stiff because __________.
(MODU = Mobile Offshore Drilling Unit. It behaves no different than a ship!)
A. M is small
B. KM is high
C. BL is small
D. KB is large
(MODU = Mobile Offshore Drilling Unit. It behaves no different than a ship!)
A. M is small
B. KM is high
C. BL is small
D. KB is large
Just like ships, a light ship has a very high center of gravity, G. It also has an extremely high metacenter,M. Together in the light condition you get a large a GM and a very "stiff" vessel.
ReplyDeleteThe best answer is Choice B.
Choices A. and D. are both FALSE.
Choice C. makes no sense.
Again, I would like to see Merchant Marine Academies include this version of questions in their classes.
Do you agree or disagree?
Good point I agree.
ReplyDeleteA large GM will give you a stiff ride.
I was leaning toward ANS: BRAVO.
Because GM=KM-KG and that means you would have to have a lot more KM.
Off on a tangent:
Question,
The deep water drill string a mile to the bottom, which is surrounded by a riser, which has buoyancy. I've often wondered how the drill string effects the stability of the rig.
All that mass / weight is way below the center of buoyancy of the Semi-sub.
It seems that they have designed that to be its own vessel in regards to stability, although it is connected to the rig.