In a friction measurement, the critical shear stress (S.) can be fitted to the following equation: Sc= 10⁹ +5 Pext [N/m²] Where Pext is the applied pressure. Considering that only adhesion and load are relevant in the analysis, determine: (a) the van der Waals pressure in the experiment and (b) the adhesion coefficient y if the equilibrium distance is 2 nm.

In a friction measurement, the critical shear stress (S.) can be fitted to the following equation: Sc= 10⁹ +5 Pext [N/m²] Where Pext is the applied pressure. Considering that only adhesion and load are relevant in the analysis, determine: (a) the van der Waals pressure in the experiment and (b) the adhesion coefficient y if the equilibrium distance is 2 nm.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter14: Fluid Mechanics

Section: Chapter Questions

Problem 81P: Prove the sped of an incompressible fluid through a constriction, such as a Venturi tube, increases...

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