13.3 Given the following information, and the Instron curve below for an axial stress experiment conducted on a sample of polyisoprene at room temperature (25 °C): Engineering Yield Stress = 48 MPa Elastic Modulus = 40 MPa Elongation at break (e) = 2.25 Ultimate Stress = 50 MPa (note 1 MPa = 1MN/m²; MN = megaNewton) = 106 N/m² Initial Sample Length = 1.5 cm (= 0.015 m) Initial Sample Cross-Sectional Area = 0.34 cm² ( = 3.4 * 105 m²) Glass Transition Temperature = look up using the macrogalleria, level 2. A. What force is applied as the polymer reaches its yield stress (in N)? B. What is the length of the polymer just before it breaks (in cm)? C. Draw a plausible stress-strain graph (preferably using software like Excel) that incorporates all of the data given above for this experiment. D. Draw a second curve (qualitatively, by hand) on top of the graph in part (C) to indicate what the Stress-strain curve would look like if the sample were tested at -90 °C instead of 25 °C. Note: glassy polymers exhibit only a small deformation after yield.

13.3 Given the following information, and the Instron curve below for an axial stress experiment conducted on a sample of polyisoprene at room temperature (25 °C): Engineering Yield Stress = 48 MPa Elastic Modulus = 40 MPa Elongation at break (e) = 2.25 Ultimate Stress = 50 MPa (note 1 MPa = 1MN/m²; MN = megaNewton) = 106 N/m² Initial Sample Length = 1.5 cm (= 0.015 m) Initial Sample Cross-Sectional Area = 0.34 cm² ( = 3.4 * 105 m²) Glass Transition Temperature = look up using the macrogalleria, level 2. A. What force is applied as the polymer reaches its yield stress (in N)? B. What is the length of the polymer just before it breaks (in cm)? C. Draw a plausible stress-strain graph (preferably using software like Excel) that incorporates all of the data given above for this experiment. D. Draw a second curve (qualitatively, by hand) on top of the graph in part (C) to indicate what the Stress-strain curve would look like if the sample were tested at -90 °C instead of 25 °C. Note: glassy polymers exhibit only a small deformation after yield.

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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