# More Fluid Mech

Tags: fluid, mech
 P: 10 hi guys. got another question for ya. ........................................ seems to of uploaded small but i explain. a reservoir is designed to retain water to a max depth of 10metres. if the water level exceeds 10 metres, then a hinged semi circle gate will open to release any excess water. the gate has a radius of 1m. the gate is hinged 9 metres below the free surface. what would be the force required to open gate? what is the depth from the free surface to the the centre of pressure. ........................................ i know the second moment of area of a semi circular surface is 0.1102R4 but not sure how to complete the question. help with working out the answer would be much appraicated so i can work back on the answer and see how to get it. thanks adzp
 Sci Advisor P: 5,096 In a general sense, you need to calculate the pressure distribution on the gate. From there, using the hinge location, you can use the area to calculate a force on the gate.
 P: 10 i cant calcluate the area as i do not know all the measurements or how would i do this? thanks adzp