Q2/ At constant strain, about 7.6 Mpa of stress is used to a polymer. After 960 h, the stress reduced to 4.8 Mpa at 30 °C. When the same polymer is heated to 50 °C the relaxation time is 1200 h. 1- Estimate the relaxation time at 30 °C? 2- Estimate the stress after 1440 h and 30 °C? 3- Estimate the stress relaxation activation energy using the equation below: 글Cor (을) Where R = 8.314 j/mol. K, and C: constant RT

Q2/ At constant strain, about 7.6 Mpa of stress is used to a polymer. After 960 h, the stress reduced to 4.8 Mpa at 30 °C. When the same polymer is heated to 50 °C the relaxation time is 1200 h. 1- Estimate the relaxation time at 30 °C? 2- Estimate the stress after 1440 h and 30 °C? 3- Estimate the stress relaxation activation energy using the equation below: 글Cor (을) Where R = 8.314 j/mol. K, and C: constant RT

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

See similar textbooks

Similar questions

What is the tensile strength of a composite fibre when its diameter is 20 microns and its critical fibre length is 30 microns? The strength between the fibre and matrix is 150 MPa.
From the matrix can you show me how the value stiffness (k) calculated?
A composite with a minimum elastic modulus of 50 GPa is to be created by mixing uniaxial epoxy with metal fibre. Calculate the minimum Elastic modulus of the metal fibre given the following data for the epoxy matrix: Elastic modulus of the epoxy matrix is 5 GPa • Volume fraction of the epoxy matrix is 0.6 A- в I U S x2 x
There are different Mechanical models that can describe the viscoelastic characteristics of a material. Discuss two of them and write the constitutive model for each.
Question 2 = 219,48 M//a = 247,3785 Pa 2.1 Consider a polymer reinforced with Spectra 1000 fibers, with a fiber volume ratio of x = 15 %. For a cross sectional area of 130 mm² and a load of 250 kg, calculate the stress in the fibers and in the matrix if the matrix material is polycarbonate. 2.2 Why are fibres capable of supporting a large portion of the tensile load in composite materials?
Big and clear handwriting with all the steps please . Make sure calculations and answers are accurate please. THANK YOU
Continuous and aligned fiber-reinforced composite with cross-sectional area of 330 mm² (0.51 in.²) is subjected to a longitudinal load of 49200 N (11100 lbf). Assume Vf=0.3, Vm = 0.7, Ef= 131 GPa and Em = 2.4 GPa. (a) Calculate the fiber-matrix load ratio. (b) Calculate the actual load carried by fiber phase. (c) Calculate the actual load carried by matrix phase. (d) Compute the magnitude of the stress on the fiber phase. (e) Compute the magnitude of the stress on the matrix phase. (f) What strain is expected by the composite? Part 1 Calculate the fiber-matrix load ratio. M Save for Later Part 2 What is the load, in N, carried by the matrix and the fibers? (a) What is the matrix load in N? i (b) What is the fiber load in N? i N N Attempts: 0 of 3 used Submit Answer
A composite material that has boron fibers coated in aluminum has a density of 2.65 g/cm^3. The fibers have a Young's modulus of 380 GPa, and aluminum has a Young's modulus of 70 GPa. The density of the fibers is 2.36 g/cm^3 and the density of the aluminum is 2.70 g/cm^3. What is the volume of the matrix? Answer:
Can you explain elastic hysteresis in polymers with the aid of a diagram?
An unknown polymer sample was found to have the following molecular weight distribution: Molecular weight range Xi Wi 8,000 – 20,000 0.05 0.02 20,000 – 32,000 0.15 0.08 32,000 – 44,000 0.21 0.17 44,000 – 56,000 0.28 0.29 56,000 – 68,000 0.18 0.23 68,000 – 80,000 0.10 0.16 80,000 - 92,000 0.03 0.05 What would the weight average molecular weight of the sample be if, we had filtered the monomer mixture with a 44 kDa dialysis tubing before preparation? (Hint: a dialysis tubing of a known molecular weight, only keeps molecules larger than that size)
There are 4 classifications of structural molecular characteristics of polymers - Linear, Network, Crosslinked. What is the final type? Answer:
Calculate the number of grams in one mole of ZnC12.6H20 (calculate molecular weight)? O=16.00 H=1.01 Zn=65.39 Cl=35.45