Properties of Fluids: Summary

The answers to the ConcepTests are given below and will open in a separate window. 
Key points from this module:
  • A fluid is a material that deforms continuously when acted upon by a shear stress.
  • A shear stress in a tangential force that acts parallel to a surface.
  • Molecular spacing is responsible for fluids to deform continuously.
  • The bulk modulus is a fluid property that describes the compressibility of a fluid.
  • Surface tension is a tensile force at interfaces of two immiscible fluids caused by an imbalance of cohesion forces.
From studying this module, you should now be able to:
  • Determine what can be considered a fluid.
  • Identify what a shear stress is.
  • Use and describe density, specific gravity, specific weight, the bulk modulus, vapor pressure, and surface tension in engineering applications.
  • Calculate the height of capillary rise.
Prepared by Janet deGrazia, Department of Chemical and Biological Engineering, University of Colorado Boulder