difference between stress and strain

The Mechanical engineering, is playing a vital role in today's Technology.
It Assist you to done things with ease, and also it brings the helpful technologies to modernize our society.

So keeping these things in mind, Lets learn about the different between stress and strain.

Lets Brief learn about stress and strain.


When some external system of forces or loads act on a body the internal forces are set up at various section of the body that resist the external forces the internal force per unit area at any section of the body is known as stress.

In S.I units the stress are usually expressed in Pascal, 

1 pascal = 1 N/m2.


Stress (6) = P/A

P = force or load acting on the body.

A = cross sectional area of the body.


When a system of forces act on a body it undergoes assembly formation this deformation per unit length is called as strain.

Strain is a dimensionless quantity, so it has no unit.


Strain (e) = ∆L/L

∆L = change in length of the body.

L = original length of the body.

Difference between stress and strain
Difference between stress and strain

Difference between stress and strain:





The applied force per unit cross sectional area, is called as stress.

The change in dimension per unit original dimension is called as strain.  


Stress is resisting force upon its area.

Strain is changed shape upon its original shape.


Stress is denoted as a Greek letter by 6 (sigma)

Strain denoted by “e”.


Mathematically, stress equal to

6 = P/A

Mathematically, strain equal to

 e = ∆ L/L


Unit of stress is N/mm2.

Strain has no units.


A body can have stress without strain. That is existence of stress without strain possible.

A body cannot have strain without stress. That is existence of strain without stress is not possible.


Because of applied stress, strain can happen.

Because of strain, stress cannot be happen.


In stress – strain diagram, stress shown on x axis.

In stress – strain diagram, strain shown on y axis.


Some of useful types of Stress are as follows.

     Tensile stress, Shear stress,         Compressive stress.

Some of useful types of Strain are as follows.

       Tensile strainShear strain, Compressive strain.

Previous Post
Next Post
Related Posts


If you have any doubt, please let me know