A ferry boat is 6.2m wide and 7.1 m long. When a truck pulls onto it, the boat sinks 6.02 cm in the water. What us the weight of the truck? The acceleration of gravity is 9.81 m/s2. Answer in units of N
The increased displacement of water, nultiplied by the weight of that water, equals the buoyancy force.
The increased displacement volume is
6.2*7.1*0.0602 = 2.65 m^3
The weight of that amount of displaced water is (density)*(water volume)*g
= 1000*2.65*9.8 = 25,970 N
That equals the truck weight