Answer
(a) The force exerted by the water on the bottom of the container is
$5.39\times 10^5~N$
(b) Since the area at the bottom of the container is larger than the area at the top of the container, the force exerted on the bottom of the container is greater than the weight of the water.
Work Step by Step
(a) We can find the gauge pressure at the bottom of the container:
$P_g = \rho~gh$
$P_g = (10^3~kg/m^3)(9.80~m/s^2)(11.0~m)$
$P_g = 1.078\times 10^5~N/m^2$
We can find the force exerted by the water on the bottom of the container:
$F = P~A = (1.078\times 10^5~N/m^2)(5.00~m^2) = 5.39\times 10^5~N$
The force exerted by the water on the bottom of the container is
$5.39\times 10^5~N$
(b) If the shape of the container was uniform from top to bottom, such as a uniform cylinder, then the force on the bottom of the container would be equal to the weight of the water. However, since the area at the bottom of the container is larger than the area at the top of the container, the force exerted on the bottom of the container is greater than the weight of the water.
