The modulus of elasticity (= Young’s modulus) E is a material property, that describes its stiffness a nd is therefore one of the most important properties o f solid materials. When a material deforms elastically, the amount of deformation likewise depends on the size of the material, but the strain for a given stress is alwa ys the same and the two are related by Hooke ́s Law (stress is directly proportional to strain):

# σ = E × ε

σ is stress

E is modulus of elasticity

ε is strain (unitless)

Elasticity module is calculated as follows; dividing stress by strain.

# E = σ / ε

**What is strain in Tension?**

Strain in tension is defined as the change of the length divided by the original (initial) length

ε = ( Δl ) / l_{o} (strain under tension)

Δl = Change in Length

l_{o }= Original Length

**How about what is the strain in Flexural stress?**

When the material is under bending load, strain is calculated as dividing the distance from the neutral axis by the curve radius.

ε = y / r (strain under bending)

### How to Calculate Modules of Elasticity?

E = Modules of Elasticity (Young's Modules)

W = Applied Load

l = distance between supports where the beam bends

w = width of the beam

h = height of the beam

d = deflection