**Young’s Modulus or Modulus of Elasticity**

It is the ratio between tensile stress and tensile strain or compressive stress and compressive strain. It is denoted by E.

E=σ/e

Where,

E – Young’s Modulus

σ – Stress

e – Strain

**Modulus of Rigidity**

It is defined as the ratio of shear stress (τ) to shear strain and is denoted by C, N or G. It is also called shear modulus of elasticity.

C,N or G=τ/es

Where,

C, N or G – Modulus of Rigidity

τ – Shear Stress

es – Shear Strain

**Bulk or Volume Modulus of Elasticity**

It may be defined as the ratio of normal stress (on each face of a solid cube) to volumetric strain and is denoted by the letter K.

K=σn/ev

Where,

K – Bulk or Volume Modulus of Elasticity

σn – Normal Stress

ev – Volumetric Strain