Question

a high youngs modulus doesnot necessarily imply that a high value of breaking stress ,why?​

Answer 1

Explanation:

SIMPLE STRESS AND STRAIN

E.J. HEARN Ph.D., B.Sc. (Eng.) Hons., C.Eng., F.I.Mech.E., F.I.Prod.E., F.I.Diag.E., in Mechanics of Materials 1 (Third Edition), 1997

1.6 Modulus of elasticity – Young's modulus

Within the elastic limits of materials, i.e. within the limits in which Hooke's law applies, it has been shown that

This constant is given the symbol E and termed the modulus of elasticity or .

Thus

(1.1)

(1.2)

Young's modulus E is generally assumed to be the same in tension or compression and for most engineering materials has a high numerical value. Typically, E = 200 × 109 N/m2 for steel, so that it will be observed from (1.1) that strains are normally very small since

(1.3)

In most common engineering applications strains do not often exceed 0.003 or 0.3% so that the assumption used later in the text that deformations are small in relation to original dimensions is generally well founded.

The actual value of Young's modulus for any material is normally determined by carrying out a standard tensile test on a specimen of the material as described below.