Chapter 6, Problem 6.28P

Interpretation Introduction

Interpretation:

The cross-sectional area of the magnesium bar is 1cm×1cm. When a force of 20,000N applied to this bar, it stretches from 10 cm to 10.045 cm. Elasticity modulus of this bar is to be calculated in GPa as well as in psi.

Concept introduction:

Concept of stress, strain and Hooke's law will be used. Formulas are given as-

$\sigma (stress)=\frac{F}{A}$

  $\epsilon (Strain)=\frac{\Delta l}{l}$

And Hooke's law-

$\sigma \propto \epsilon$