To calculate the water pressure that acts on the hull of the boat, we can use the equation:
Pressure = Force / Area
The force acting on the hull is the buoyant force, which is equal to the weight of the water displaced by the boat. Since the boat is floating, the weight of the water displaced is equal to the weight of the boat. Therefore:
Force = Weight of boat = 20,000 N
The area of the hull that is in contact with the water is 4 m2
Therefore, the water pressure acting on the hull of the boat is:
Pressure = Force / Area = 20,000 N / 4 m2 = 5000 N/m^2
The pressure unit is Newtons per square meter (N/m^2) also known as Pascals (Pa).
It's important to note that the weight of the boat and the water displaced are in Newtons and the area of the hull is in square meter, that's why the pressure is in N/m^2.