Area of the topside of the sheet metal is 10 square feet.

Sheet metal is submerged horizontally in 8 feet of water.

Depth of the water 8 ft.

Fluid force on metal sheet .

Where Fluid force, pressure of an object and  Submerged horizontal surface area.

Pressure of an object at depth  in a liquid is .

Where weight density of liquid.

Here liquid is water, for water  pounds per cubic foot.

Substitute  and  in .

Pressure of object  pounds per square feet.

Submerged surface area  square feet.

Substitute  and  in .

Fluid force on top side is  lb.

Fluid force is  lb.