What is meaning of Metacentre?

Metacentre is at the intersection of vertical lines through the centres of buoyancy in the initial  and slightly inclined positions.

• The transverse metacentre (M) is used when transverse inclinations (heel and list) are considered.
• The longitudinal metacentre (ML) is used when longitudinal inclinations (trim) are considered.
• Metacentric Height (GM) is the distance between the centre of gravity and the metacentre.

The position of the metacentre may be calculated from the formula.

BM = (I/V)

where ,   I  is the moment of inertia of the waterplane in metre4 units
V is the volume of displacement in cubic metres.

Note:

The moment of inertia, which is also called the second moment of area, of a body about  line can be obtained by multiplying the mass of each and every particle in the body by the square of its distance from the line about which the moment of inertia is required. Adding the quantity found for each and every particle in the body gives the moment of inertia of the body.