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Answer this question using your laboratory measurements and the Excel calculations and analysis template corresponding to the Bernoulli equation lab using the Venturi pipe. You're expected to have completed all calculations and plots before attempting this question.
", "advice": "In order to convert a pair of volume, V (l), and time T (s) measurements into m3s-1 we need to use the appropriate volume conversion, 1000 l = 1m3, and the fact that Q = V/T.
\nTherefore, using example values, V(l)/1000/T(s) = Q (m3s-1) = {V}/1000/{T} = {Q}
\nGiven that we now know Q (which is constant for the whole system), we can calculate flow velocities at all tapping points using Q (m3s-1) = uA, where u is average flow velocity (ms-1) and A is cross-sectional area (m2).
\nFor tapping position E we're given A as 78.5x10-6 m2, therefore: u (ms-1) = Q/A = {Q}/78.5x10-6 = {v_e}
\nAs shown in the lab material, the theoretical static head at a given tapping position is given by:
\n\nThis considers no energy losses throughout the system, therefore static head will be equal to initial total head, HA (m), minus velocity head at this position. Using example data we have:
\nTheoretical static head = {h_t}-{v_e}^2/(2*9.81) = {h_theo} (m)
\nFor advice on parts c) and d) refer to the revealed answers above.
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\nEnter the volume measured at the high flow bench (l): [[0]]
\nEnter the average time (s) to fill this volume: [[1]]
\nEnter the corresponding flow rate (m3s-1): [[2]]
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\nWhat is the experimental static head at tap A, hA(m): [[0]]
\nWhat is the calculated initial total head at tap A, HA(m): [[1]]
\nFor tapping position E:
\nObserve the resulting plots and match each curve with its corresponding description:
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