Chapter 1, Problem 1.5.4P

The strength-to-weight ratio of a structural material is defined as its load-carrying capacity divided by its weight. For materials in tension, use a characteristic tensile stress obtained from a stress-strain curve as a measure of strength. For instance, either the yield stress or the ultimate stress could be used, depending upon the particular application. Thus, the strength-to-weight ratio R_S/Wfor a material in tension is defined as

   $R_{s/w}=\frac{\sigma }{\gamma }$

in which a is the characteristic stress and 7 is the weight density. Note that the ratio has units of length. Using the ultimate stress ${\sigma }_U$as the strength parameter, calculate the strength-to-weight ratio (in units of meters) for each of the following materials: aluminum alloy 606I-T6, Douglas fir (in bending}, nylon. structural steel ASTM-A57.2, and a titanium alloy. Obtain the material properties from Tables [-1 and 1-3 of Appendix I. When a range of values is given in a table, use the average value.