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## Homework Statement

A cube of side 0.3m which has an average density of 4500 kg/m^3 . Determine the overall force acting on the cube when it is submerged in water.

Density of water is given to be 1000 kg/m^3

## Homework Equations

[itex]

p=h \rho g \\

[/itex]

Upthrust = [itex] \rho g V = \rho g l^3 [/itex]

## The Attempt at a Solution

The main reason I am confused is because I thought one would need to know the depth, h, the cube is submerged at?

I understand that one only needs to consider the forces acting on the top face and bottom face because the others cancel out but again, I have no idea how I am supposed to do that without knowing the depth.

Is it simply that the total force is equal to the upthrust? Because that's the only equation I can think of that does not include the depth.

If so then it is simply

[itex] \rho g l^3 = 4500 \times 9.81 \times 0.3^3 = 1192 N [/itex]

Also, is there a symbol used to represent upthrust or is it simply something like F with a subscript?

Any help appreciated. Thanks :)