Page 46 - statbility for masters and mates

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Ship Stability for Masters and Mates
in salt water of density 1025 kg per cubic metre.
New draft Old density Old draft New density
New draft Old density Old draft New density
Ans. New draft 2:09 m
Example 2
1020 2:1 m 1025
2:09 m
A box-shaped vessel ¯oats upright on an even keel as shown in fresh water of density 1000 kg per cu. m, and the centre of buoyancy is 0.50 m above the keel. Find the height of the centre of buoyancy above the keel when the vessel is ¯oating in salt water of density 1025 kg per cubic metre.
Note. The centre of buoyancy is the geometric centre of the underwater volume and for a box-shaped vessel must be at half draft, i.e. KB 12 draft.
Fig. 5.1
In Fresh Water
KB 0:5m, and since KB 12 draft, then draft 1m In Salt Water
New draft Old density Old draft New density
New draft Old draft Old density New density
1 1000 1025
New draft 0:976 m New KB 12 new draft
Ans. New KB 0:488 m, say 0.49 m.