Q1) Find the force exerted by a jet of water of diameter 75 mm on a stationary flat plate, when the jet strikes the plate normally with a velocity of 20 m/s.

Solution: Given:

i) Diameter of jet, d = 75mm = 0.075mm

ii) Area, $a = \dfrac\pi4d^2 = \dfrac\pi4(0.075)^2 …