Question

A 4 m high and 1 m wide reservoir is used to collect rainwater (SG = 0.98) for the purpose of plantation. The reservoir is equipped with a discharged conduit in order to prevent overflow as shown in Figure Q2(b). A circular plate with a radius of 50 cm is used as a gate at the end of the conduit and hinged to point A. Determine the force (F) required to withstand the amount of pressure at the center of the gate when the reservoir is full. 2.5 m rainwater KO

Answer 1

2.5m hiven Height (h): 4m width (b) = lm S.C. - 0.98 radius of gately)Som 20.5m Hydrostatic force act on circular gute (fr) Joism - k FH a Pg YeXA distance of C.G. Of gate from free surface water Az Area of circular plate = 70? A = 7*0.52 fre= 0.988103 x 9.81x2.5 x 7X0.52 FH 18876.65 N this force will act at Centre of pressurelye) and we know that - Yp = Yet AC de xxc - Yo = Y(+ 168Yc Yo = 25 + 0.52 4x2.5 Yo = 2.525 m

FBD of Circular gute Yo and Yp distance between is ah Ah= Yo-Ye. _ = 2.525-22.5 .P Ah = 0.025m Equating the Moment about Point À by both the Forces we get FHX (o-on) = F xx 18876.68x60.5-0.025 ) = fx0.5 And [F: 11932.82 N