$=9\mathrm{.}81k\frac{N}{m^3}$

$g=9\mathrm{.}81\frac{m}{s^2}$

Problem $1$: The horizontal rectangular channel is shown in the following figure. It is $10$ m wide and $2$ m deep, and the width gradually contracts to $8$ m $.$ During the contraction, the water also flows up a stage of $1$ m $,$ i$.$e$.,$ the floor of the water increases elevation by $1$ m $.$ If the water flows at $200\frac{m^3}{s}.$ Determine the depth of water at $8$ m wide section.