OUESTION $4[20$ MARKS$]$

$($a$)$ Figure $4$ shows the fluid gate structure that holds water with surrounding temperature $25C.$ A fluid have $4m$ depth and width of rectangular opening door is $0\mathrm{.}9m.$ Calculate the forces on the hinge and stopper. Sketch the free body diagram. Given $x$ is $1\mathrm{.}9m.$

Figure $4$: A Fluid Gate Structure

$[15$ Marks$]$

$($b$)$ Based on Hazen$-$Williams concept, compute a head loss of $120mm$ concrete pipe that carry $0\mathrm{.}0090\frac{m^3}{s}$ of water over a length of $250m.$

$[5$ Marks$]$