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Question 2511Deck Safety70% to pass

The liquid mud tanks on your vessel measure 20'L by 18'B by 7'D. The vessel's displacement is 986 T and the specific gravity of the mud is 1.6. What is the reduction in GM due to a pair of these tanks (p/s) being slack?

AI Explanation
The correct answer is C) .88 foot. The reduction in GM (metacentric height) due to a pair of slack liquid mud tanks (port and starboard) can be calculated using the formula for free surface effect. The free surface effect is the reduction in GM caused by the movement of the liquid inside the tanks as the vessel rolls. The formula is: Reduction in GM = (ILT / Δ) * (1 - (ρ / SG)), where ILT is the moment of inertia of the free surface, Δ is the vessel's displacement, and ρ and SG are the density and specific gravity of the liquid, respectively. Given the dimensions of the mud tanks and the vessel's displacement and the mud's specific gravity, the calculated reduction in GM is .88 foot, which matches the correct answer choice C.

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