Stability – I : Chapter 8

4. A triangular shaped vessel floats in SW. Her water plane is a rectangle 40m x 12m. If her KB is 3.6m, find her displacement .

Solution :

Water plane area = (L x B)
= 40m x 12m

Initial KB =3.6m,

As we know that centeriod of triangle is 2/3^rd of the perpendicular bisector of the base .hence centre of buoyancy will be always 2/3^rd of perpendicular bisector of base.

So, KB = 2/3 x (Draft)
3.6    = 2/3 x d

So, Draft(d)  =(3.6 x 3 / 2)
= 5.4m

We know that:
Volume of triangular vessel =   ½ ( L  x B x  H)

Displacement =(u/w volume) x (density)
= ½  (L x B x d) x (1.025)
= 1/2  (40 x 12 x 5.4) x (1.025
= 1328.4t .