Question

A cylindrical specimen of brass that has a diam- eter of 20 mm, a tensile modulus of 110 GPa, and a Poisson’s ratio of 0.35 is pulled in tension with force of 40,000 N. If the deformation is totally elas- tic, what is the strain experienced by the specimen?

Answer 1

Answer:

strain = 0.0011575

Explanation:

Given:

- The diameter of specimen d = 0.02 m

- Applied uni-axial force P = 40,000 N

- Modulus of Elasticity E = 110 GPa

Find:

If the deformation is totally elastic, what is the strain experienced by the specimen?

Solution:

- First we need to calculate the stress in the specimen using the relation:

                                        stress = Force / Area

                                        stress = 40,000*4 / pi*d^2

                                        stress = 160,000 / pi*0.02^2

                                        stress = 127.323 MPa

- Now compute Elastic strain from the definition of Elastic modulus of a material:

                                       E = stress / strain

                                       strain = stress / E

- Plug in the values:  

                                        strain = 127.323 / 110*10^3

                                        strain = 0.0011575