Question $9.$

$9\mathrm{.}1$ A $10$ mm diameter sharp$-$edged orifice is provided in the vertical side of a water tank. The

centre line of the orifice is $750$ mm below the water level. The set of water issuing in a

horizontal direction reaches a horizontal distance of $550$ mm and falls $128$ mm vertically.

The set diameter of the vena contract is $9$ mm $.$ Assume that the water in the tank remains

constant.

Calculate the following:

$9\mathrm{.}1\mathrm{.}1$ The coefficient of delivery $(cd)$

$9\mathrm{.}1\mathrm{.}2$ The coefficient of velocity $($cv$)$

$9\mathrm{.}1\mathrm{.}3$ The coefficient of contraction $($cc$)$

$9\mathrm{.}1\mathrm{.}4$ The time taken, in seconds, to discharge $50$ litres of water from the tank.

$9\mathrm{.}2$ A venturi meter with a throat diameter of $160$ mm is placed in a pipe with a diameter of

$260$ mm $.$ The discharge rate of the pipe is $135$ litres per second. Assume that the coefficient

of delivery being used is $0,97$ and that the venture meter is equipped with a mercury

manometer. Calculate the mercury head in the manometer.