Hooke’s Law:

There is a certain limit of deforming forces up to which the behavior of a body remains elastic. This is called the elastic limit of the material of the body.

Within this elastic limit, the stress is proportional to the strain. i.e, \( stress\ \alpha\ strain \), i.e, \( \frac{stress}{strain}=constant \). This is known as Hooke’s law. The constant is called the Modulus of Elasticity.

The dimension and unit of elastic modulus are the same as that of the stress.

Its dimension is \( [ML^{-1}{T^-2}] \).

Its units are \( N/m^2 \) (S.I.), \( dyne/{cm}^2 \) (c.g.s.), \( poundal/{ft}^2 \) (f.p.s.).