... averagevelocity to be known. The use of Q* for practical problem solving is describedin the following illustrative example. 10 4 10 5 10 6 10 7 10 8 10 9 10 10 10 11 10 12 10 -3 10 -2Dimensionless flowrate ... head, V2 1 /2 D 1 /D2Contraction<45Re 1 < 2500 Kf 1: 6 (1: 2 16 0Re 1 )(4À 1) sin(/2)Re 1 > 2500 Kf 1: 6(0:6 1: 92f 1 )2(2À 1) sin (/2)45 18 0Re 1 < ... 2.20directly: 1 fp 1: 768 ln 0 1: 252DÃ3=2 15 :79f 0:004 01 Re DÃ3=2Â 1 fp 9:487 10 3Â 15 :79 1: 5 10 5"V RefDf 1: 5 Â 10 5Â 0:0 01 0 :1 Â 10 00 1: 5m=sQ 4D2"V...