Casio fx-7400G PLUS Booklet

Also see for fx-7400G PLUS: User guide Product catalogue Specifications Specifications Programing manual

– 35 –Results (Example)Graphic Calculator Operation2-1. Determination of Maximum ValueAs in 1-1 and 1-6 of EC-1(Density of a Liquid), select the STAT Mode, input the data, and drawthe regression curve.This type of “viscosity measurement graph” exhibits a quadratic curve form. By determining themaximum value (peak) of this regression curve yields the concentration at which maximumviscosity is achieved as well as the viscosity at that point.As in 1-8, display the graph of the regression expression copied to thegraph menu and then press !1(TRCE) to move the cursor toX = 52.82. This reveals that the maximum value of Y is 1.5197.You can also obtain the maximum value as shown below.Quadratic Regression Valuesa = –2.901 10–4, b = 0.03052, c = 0.7179CalculationEC-2 Viscosity of a LiquidMeasuring the Viscosity of a LiquidSolutions of ethanol and water are prepared in concentrations of 0, 20, 40, 60, 80, and 100wt%. An Oswald viscometer is used to measure the flow time and determine the viscosity ofeach sample. Results are used to create and study a concentration - viscosity curve.Exercise0 0.719220 1.18040 1.53360 1.51180 1.239100 0.900EthanolConcentration (wt%)Viscosityη (mPas)– b = – 0.03052 = 52.62a 2 (–2.90110–4)y = 2ax + b = 0 → x =– b2a