For some viscoelastic polymers that are subjected to stress relaxation tests, the stress decays withtime according toa(t) = a(0) exp(-4)(15.10)where σ(t) and o(0) represent the time-dependent and initial (i.e., time = 0) stresses, respectively, and t and T denoteelapsed time and the relaxation time, respectively; T is a time-independent constant characteristic of the material. Aspecimen of a viscoelastic polymer whose stress relaxation obeys Equation 15.10 was suddenly pulled in tension toa measured strain of 0.5; the stress necessary to maintain this constant strain was measured as a function of time.Determine E (10) for this material if the initial stress level was 3.5 MPa (500 psi), which dropped to 0.5 MPa (70psi) after 30 s.

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Answered: For some viscoelastic polymers that are…

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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