Necking occurs when the applied load ceases to increase, i.e. when the nominal stress-strain curve peaks.
The elastic modulus of the composite material is given by:
E = E_c f + E_s (1-f)
TS = TS_inf - (A/Mn)
Solving the system of equations to find TS_inf and A.
One reason for the lack of interessest in defects in polymers might be that they are less critical due to the macro-scale molecules of the polymer. The point defect concept is different in polymers than in metals due to the chainlike macromolecules and the nature of the crystalline state for polymers.
Other reasons might be that polymers are often used for low stress applications, while metals are preferred for load bearing applications, or that there has been done less research on polymers than metals in general.
Crystal polystyrene is not crystalline, it is completely amorphous.
a) See derivation in appendix
Size teaspoon = 4.93 mL +/- 5%
Size acre = 4046.86 m +/- 20%
- where the ucertainties are guesses
The order of magnitude of the results are belivable. However it is difficult it is difficult to determine the uncertenties of the measured volume and area, as unconventional units are used. Therefore quite large uncertenties are used, making the uncertenty of the result noteble as well.