A specimen of some metal having a rectangular cross section 10.4 mm × 12.8 mm is pulled in tension with a force of 15900 N, which produces only elastic deformation. Given that the elastic modulus of this metal is 79 GPa, calculate the resulting strain.

Respuesta :

Answer:

[tex]\sigma=0.00151[/tex]

Explanation:

We apply Hooke's Law as follows :

[tex]\sigma= E\varepsilon[/tex]

where [tex]\sigma[/tex] is the applied stress

#The applied stress is also equal to :

[tex]\sigma=\frac{F}{A_o}=\frac{F}{lw}[/tex]

Where [tex]l\[/tex] and [tex]w[/tex] are the cross-sectional dimensions.

=>We equate the two stress equations:

[tex]E\varepsilon=\frac{F}{lw}\\\\\varepsilon=\frac{F}{Elw}[/tex]

#We substitute our values in the equation as:

[tex]\varepsilon=\frac{15900\ N}{(79\times 10^9\ N/m^2)(10.4\ m\times 10^{-3}\times 12.8\ m\times 10^{-3})}}\\\\\\=0.00151[/tex]

Hence, the resulting strain is 0.00151