Problem $3$

After an early summer flooding, water level in a river rose and submerged a tank used for storing chemicals. The tank has a rectangular opening gate that is hinged at the upper edge $($A$).$

$($a$)$ If the stop at the bottom of the gate can develop a maximum force of $1764N,$ determine the level of water above the hinge $(H),$ at which the gate is at the threshold of being opened.

We give $L=0\mathrm{.}6m,W=0\mathrm{.}2m$ and $g=9\mathrm{.}8\frac{m}{s^2}$

$($b$)$If the gate is made of a material that shatters when it is subjected to a normal stress exceeding $40$kPa at any point. As the flow level rises above point $A,$ what will happen first, the shattering of the gate or the yielding of the stop?