What is Stress | Difference Between Stress and Strain | What is Strain ? Stress & Strain formula |What is Stress in Engineering Mechanics | Unit of Stress

 

  -:  Difference between STRESS and STRAIN :-

Stress :-

• Stress is the intensity of internal resisting forces (to oppose the applied pressure) developed at a point. 
• in other words - it is a internal resistive force to deformation per unit area.
• Stress may act either normal or parallel to the surface. 
• Magnitude  of the stress at a point is unequal in all the directions.
• Stress can be Tensile, Compressive or Shear type.
• Due to stress Pressure will not be developed.

           Stress = F/A         in N/meterSq.

where F = internal resistive force developed (external)  in N

                                       A = Area in  meterSq. 

Strain:-

• The ratio of change in length to actual length is called Strain.

• When a force get applied on the body, length of that body either increases or decreases.

• If length of body increases means the applied force is Tensile(+F) where if length decreases means the applied force is Compressive(-F) in nature.  

• In other words, The ratio of Change in dimension to the Original Dimension is called Strain.

                            Strain(ε) =   ΔL/L  = (L1 - L)/L

                    Where  ΔL = change in length

                                   L = actual length.

                                 L1 = New Length after force applied.

 

[Note:-  in case of compressive force, Direction of forces shown in the figure will be inward.]

 Difference between Pressure & Stress ? 

Difference between Frame & Chassis ?

 

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