What's the volume of water required inside the lock if.... The dimension of the lock is:40 long x 3.5 height x 6 width allowing 0.5 height. The ship weights 400T plus 300T(LOAD) total= 700T whats the amount of water used per lock allowing allowing 0.5 m from the height? What if the ship empties its load on the lock ? the density of the load is 755kg/m^3. 2. Relevant equations Archimedes principle Mass of water displaced 3. The attempt at a solution Mass of water displaced by the boat mass = 700T VOLUME = 700M^3 Total volume inside the lock allowing 0.5 (3x40x6)m^3 - 700M^3 Is that correct ? How about if the ship empties its load on the lock ?