Fig., shows the stress-strain curve for a given materal. What are (a) Young's modulus and (b) approximate yield strength for this material?

Explanation

It is clear from the given graph that for stress 150 `xx10^(6)"N"//"m"^(2)` , strain is 0.002.
`therefore` Young's modulus, Y = `("Stress")/("Strain")`
`=(150xx10^(6))/(0.002)=7.5xx10^(10)"N"//"m"^(2)`
Hence, Young’s modulus for the given material is 7.5 `xx10^(10)"N"//"m"^(2)`.
(b) The yield strength of a material is the maximum stress that the material can sustain without crossing the elastic limit.
It is clear from the given graph that the approximate yield strength of this material is
`300xx10^(6)"N"//"m"^(2)or3xx10^(8)"N"//"m"^(2)`