Question

a crane having steel ropes is used to lift heavy load upto 10000 kg. the elastic limit for steel is 3*10⁸ N/m². what should be the radius r of the steel rope used?

Answer 1

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