To solve this problem we will apply the conversion concepts given for the available units. Recall that the unit 'psi' is the expression equivalent to pounds per square inch applied on a surface. The force pounds in Newtons (mass per acceleration) are equivalent to
[tex]1lb = 0.45kg*9.8m/s^2[/tex]
While square inches to square meters are equivalent to
[tex]1 in^2 = 0.00064516m^2[/tex]
Making the conversion for the elimination of the units we would have
[tex]\sigma = 21600psi[/tex]
[tex]\sigma = 21600\frac{lb}{in^2}[/tex]
[tex]\sigma = 21600\frac{lb}{in^2}(\frac{0.45kg*9.8m/s^2}{1lb})(\frac{1in^2}{0.00064516m^2 })[/tex]
[tex]\Rightarrow \therefore \mathbf{\sigma = 147647095.3Pa}[/tex]
[tex]\Rightarrow \therefore \mathbf{\sigma = 147.64Mpa}[/tex]
