My teacher is very strict about copying his work so I will have to explain it.
We have a wall with two fluids of different constant densities and depths. The wall is 'L' long. The wall has a section that goes sideways a certain depth in and then down all the way to the bottom of the tank. We have already solved for the pressures as a function of z on both sides. Previous exercises had us find the resultant force on different sections of the wall. Now we are asked to find the torque on the lower portion of wall about point P.
I see that 2 things will be changing with z - the pressure force exerted from both fluids and the moment arm. I am not too great with integration - If I could get pointers on where to start with my integration that would be appreciated. .