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**1) An aquarium tank is 80cm long, 30cm wide, and 35cm deep and is filled to the top. What is the force of the water on the bottom of the tank, with dimensions 80cmx30cm, AND the force on the front window with dimensions 80cmx35cm, respectively?**

For the first part, is the question actually asking for the

*normal force*on the tank's bottom exerted by the water, or is it asking for the total weight of the water? Are these 2 values equal? If so, why?

By the way, I tried to use Force = pressure x area

=(p_o + rho*g*d) x area

=(101300+1000*9.8*0.35) x 0.8m x 0.3m

=25135.2N <----but this is not what I got when I calculate the weight of the water, how come their values are different? I don't see why...

Also, can someone help me on the second part? I know that this needs integration and I know that for a liquid, the pressure of WATER at a depth d is p=p_o+(rho)(g)(d), but in this case, what is the value for p_o? p_o=p_atm=101300Pa because there is air above the water, right?

(Note: This is not a homework question anymore. I did it for practice and to understand the major concepts of fluid mechanics!)