Fig. 8.43. The forces of buoyancy and gravity affect stable and unstable ships. (A) A stable ship in calm water with its center of gravity (CG) and center of buoyancy (CB) positions marked. (B) An unstable ship with unevenly distributed density cannot tilt itself back upright. (C) A ship with a weighted hull (uneven density) in calm water. (D) An unstable ship with a weighted hull (uneven density) that cannot right itself from a tilted position.
Image by Byron Inouye