The discussion on kinematics and balance laws has been completed in previous units. In this lesson, the focus will be on constitutive relations. These relations tell us what is solid and, what is fluid. What basically makes a material one or the other? The equations discussed in all the previous lessons are revisited to see the number of equations and the number of unknowns to motivate the study of constitutive laws.
In this video we will answer the following question: