Question

An 800 ft ship has a displacement of 35,000 tons, and the

area defined by the waterline is 38,000 ft2

. Will the ship take

more or less draft when steaming from salt water to fresh water?

How much will it settle or rise?

Answer 1

$\rho _s>\rho_f,$ it will settle.

$V=Sh,$

$F_A=\rho_1 gV_1=\rho_2gV_2,$

$\rho_1Sh_1=\rho_2Sh_2=m,$

$\Delta h=h_1-h_2=\frac mS(\frac 1{\rho _1}-\frac 1{\rho_2})=26~cm.$