Chapter 9 sol
Subject:
Physics [1]
Chapter 9 Page 9.1 9 Solids and Fluids PROBLEM SOLUTIONS 9.1 The elastic limit is the maximum stress, F A where F is the tension in the wire, that the wire can withstand and still return to its original length when released. Thus, if the wire is to experience a tension equal to the weight of the performer without exceeding the elastic limit, the minimum cross-sectional area is 2minmin 4 D F mgA elastic limit elastic limit ?? ? ? and the minimum acceptable diameter is ? ? ? ? ? ? ? ? 2 3min 8 4 70 kg 9.8 m s4 1.3 10 m 1.3 mm5.0 10 Pa mgD elastic limit? ? ?? ? ? ? ?? 9.2 (a) In order to punch a hole in the steel plate, the superhero must punch out a plug with cross- sectional area, csA , equal to that of his fist and