Hydraulic Diameter

Water flows through a $56-cm$ diameter round pipe, but the pipe is only partially filled. Consider the

three cases shown below, where the pipe is $($a$)$ less than half$-$filled, $($b$)$ exactly half$-$filled, and $($c$)$ more

than half$-$filled. Determine the hydraulic diameter in each case $($note: a very simple expression for the

hydraulic diameter of a half$-$filled pipe was given in the lectures$).$ Angles are shown to make the calcu$-$

lations easier $($you could have found them using trigonometry, obviously$).$