Question

(a) Define longitudinal center of gravity (LCG) and longitudinal centre of buoyancy (LCB). (6)

(b) The immersed cross-sectional areas of a ship 120 m long, commencing from aft are 2, 40, 79, 100, 103, 104, 104, 103, 97, 58 and 0 m2. Calculate: (10)

(i) Displacement

(ii) Longitudinal position of the centre of buoyancy.

Answer 1

Part (a)

Longitudinal Centre of Gravity (LCG):

The Longitudinal Centre of Gravity (LCG) is the point along the length of the vessel where the total weight of the ship is considered to act vertically downward.
It represents the balance point of the ship's weight distribution and is measured as a distance forward or aft of the midship.

Longitudinal Centre of Buoyancy (LCB):

The Longitudinal Centre of Buoyancy (LCB) is the point along the length of the vessel through which the total buoyant force, acting vertically upward, is considered to act.
It represents the balance point of the underwater volume of the ship and is also given as a distance forward or aft of the midship.

✓ Verified Model Answer (Text Solution)

Longitudinal Centre of Gravity (LCG):