Question

The yield point of a typical solid is about 1%. Suppose you are lying horizontally and two persons are pulling your hands and two persons are pulling your legs along your own length. How much will be the increase in your length if the strain is 1%? Do you think your yield point is 1% or much less than that?

Answer 1

Let my length = L
Let the increase in length = l
Strain
$$\begin{gathered} =\frac{l}{L}=\frac{1}{100} \\ \Rightarrow l=\frac{L}{100} \\ \mathrm{So},\mathrm{the}\mathrm{increase}\mathrm{in}\mathrm{length}\mathrm{will}\mathrm{be}\frac{L}{100}. \end{gathered}$$

Yes, the yield point is much less than the 1% strain because the human body consists of joints and not one uniform solid structure.