A spider of mass 6.4 10-4 kg hangs from a 72.2-cm-long thread whose diameter is 2.0 10-3mm. Young’s modulus of thread is 3. 109 N/m2. By how much does the thread stretch?
Calculate the force a piano tuner applies to stretch a steel piano wire 7.00 mm, if the wire is originally 0.890 mm in diameter and 1.35 m long. Young’s modulus for steel is 210*109 N/m2.