Survey

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Questions When the jet which strikes the plate is directed upward, the velocity in the jet decreases with increasing height. Assuming no influence of the plate on the velocity, derive an expression for the velocity vs. height above the nozzle. Note that such an analysis is truly only applicable for the flat plate (since the jet entry and exit elevations for the curved surface are equal). For distances such as those in the lab, what percentage change in velocity will occur? (Use Bernoulli’s equation) P1=P2=0 Therefore (V12)/ (2g) + Z1 = (V22)/ (2g) + Z2 Velocity at max height equals V2 = (V12-2g (Z2+ Z1)) 1/2 Trial#1 (Flat Surface) V2 7.61787 7.429842 6.916726 6.468677 5.510997 4.717019 4.001936 2.287144 -% Change 0.586457 0.616239 0.710053 0.810589 1.111699 1.508303 2.077294 5.980916 A jet of water issues from a 2-inch diameter nozzle pointed directly down onto a flate plate located 14 feet below. Velocity at the nozzle is 60 ft/s. What force is exerted on the plate? V2=Vo2+2*g*x V= ((60ft/s) 2 +2*32.2 ft/s2* 14 ft = 67.09396396 ft V= 67.1 ft/s

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