A paper clip is made of wire 0.5 mm in diameter. If the original material from which the wire is made is a rod 25 mm in diameter, calculate the longitudinal engineering and true strains that the wire has undergone during processing.

Respuesta :

Answer:

Engineering strain =2499

True strain = 7.82

Explanation:

Given that

Initial diameter D= 25 mm

Final diameter = 0.5 mm

As we know that ,the volume of material will remain constant

[tex]A_iL_i=A_fL_f[/tex]

[tex]\dfrac{\pi }{4}D^2L_i=\dfrac{\pi }{4}d^2L_f[/tex]

So now by putting the values

[tex]\dfrac{\pi }{4}\times 25^2L_i=\dfrac{\pi }{4}\times 0.5^2L_f[/tex]

[tex]\dfrac{L_f}{L_i}=2500[/tex]

We know that

[tex]Engineering\ strain=\dfrac{L_f-L_i}{L_i}[/tex]

[tex]Engineering\ strain\ e=\dfrac{2500L_i-L_i}{L_i}[/tex]

e=2499

We also know that

[tex]True\ strain=\ln\left ( 1+e \right )[/tex]

[tex]True\ strain=\ln\left ( 1+2499 \right )[/tex]

True strain = 7.82