Answer:
[tex]227046.75\ \text{N}[/tex]
Explanation:
h = Depth = 30 m
[tex]\rho[/tex] = Density of seawater = [tex]1030\ \text{kg/m}^3[/tex]
A = Area = [tex]0.75\ \text{m}^2[/tex]
W = Weight = [tex]300\ \text{N}[/tex]
g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
The force balance of the system is given by
[tex]F=\rho ghA-W\\\Rightarrow F=1030\times 9.81\times 30\times 0.75-300\\\Rightarrow F=227046.75\ \text{N}[/tex]
The downward force required to open the hatch is [tex]227046.75\ \text{N}[/tex].
