The following table gives the area of a ship’s water-plane at various drafts: Draft (m) 6 7 8 Area (sq. m) 700 760 800 Find the volume of displacement and approximate mean TPC between the drafts of 7 and 8m.

The following table gives the area of a ship’s water-plane at various drafts:

 Draft (m)     6          7          8

 Area (sq. m)    700 760     800

Find the volume of displacement and approximate mean TPC between the drafts of 7 and 8m.

Reference: Ship Stability for Masters & Mates (6^th edition), Exercise – 10.11

 

Solution:

Volume = h/12 * (5y₁ + 8y₂ – y₃)

              = 1/12 * (5*800 + 8*760 – 700)

              = 781.67 m³

TPC = A_w*1.025/100

        = 781.67*1.025/100

        = 8.01 ton/cm