Viscosity and Shear Stress: ConcepTest and Example Problem

Try to answer this ConcepTest and solve this example problem before using this module. Studies show that trying to answer the questions before studying material improves learning and retention. By the end of this module, you should be able to answer these on your own. Answers will be given later in this module.

A practice problem for a Viscosity and Shear Stress self study module
Example Problem

A toothpick is placed inside a 5 mm diameter straw full of a mysterious fluid with a gap of 1 mm between the toothpick and the straw. If 50 mm of the toothpick is pulled from the straw with a force of 0.1 N such that the toothpick moves with a constant velocity of 0.1 m/s, what is the viscosity of the fluid? Assume the fluid is Newtonian and velocity profile is linear.