Question

a crane having steal ropes is used to lift heavy weights upto 10⁴kg. the elastic limit of the steel is 3.8x10^-8Nm^​_1. what should be the radius of the rope?

Answer 1

$$\begin{gathered} Masstobelifted=10000kg=M \\ Force=Mg=10000*9.8=98000N \\ \mathrm{elastic}\mathrm{limit}f\mathrm{or}\mathrm{steel}is3*{10}^{8}N/m^2 \\ So, \\ \mathrm{elastic}\mathrm{limit}=Force/Area \\ =98000N/\pi R^2 \\ R=0.0101m \end{gathered}$$