Tracker-aided experiments for the determination of viscosity coefficients of liquids using the communicating vessels method with weighted regression analysis

Abstract

Tracker-aided experiments using communicating vessels have been performed to determine the viscosity coefficients of liquids at room temperature with weighted linear regression analysis. The calculation involves weighted linear regression analysis of -ln[(2z1/z0) - 1] against time, where z1 and z0 are the instantaneous liquid level and the initial liquid level in one of the vessels with the higher initial liquid level, respectively, and a computer-aided χ2 goodness of fit test. Based on the maximum Reynolds number obtained, it is concluded that the liquid flow was laminar, as required by the theory. From the χ2 goodness of fit test it is concluded that the relation between -ln[(2z1/z0) - 1] and time is linear, in agreement with theory. As samples, water and rectified spirit were used. The viscosity coefficients of both liquids obtained from experiments using various capillary tube sizes agreed with accepted values.