Question

4. A nylon rope used by mountaineers elongates 1.10 m under the weight of a 65.0-kg climber. If the rope is 45.0 m in length and 7.0 mm in diameter, what is Young's modulus for nylon?

Answer 1

$$\sigma=\varepsilon E$$

$$F/A=E\Delta l/l_0$$

$$E=l_0 F/(A\Delta l)\\ =45.0*65.0*9.81/(3.14*(3.5*10^{-3})^2*1.10)\\ =6.78*10^8\:\rm Pa$$