Tensile force question

[Guest richard cates]

A component in a car suspension system is subjected to a tensile force of 20kN. The component is manufatured from a hollow steel tube of externel dia 25mm and wall thickness of 4mm. The modulus of elasticity (E) for the steel is 209 GN/m squared.

 

a/ calculate the cross-sectional area of the component in mm

b/ calculate the direct stress on the component in MN/m squared

c/ find the direct strain on the component.

d/ if the component is 30cm long calculate the change in length of the component under the applied load. give answer in mm.

e/ if the yield strength of the material is 420MN/m squared, calculate the factor of safety for the component.

 

Could someone please show me how to answer this question. I am pulling my hair out. Thanks.