A solid may change its dimensions in 3 different ways, resulting in 3 types of stress (1) Longitudinal stress (Tensile and Compressive stress) (2) Tangential or Shearing Stress, and (3) Hydraulic stress.
Let’s find out the details of these stresses, as per the class 11 physics syllabus.
Longitudinal stress [Tensile and Compressive stress]
Longitudinal stress can be of 2 types: Tensile stress and Compressive stress.
When forces are applied at a right angle to the cross-sectional area or surfaces to either elongate or compress the object, then these forces tend to cause a change in the length of the solid body and generate Longitudinal Stress. As said this stress may be of 2 types, tensile and compressive.
Tensile stress tends to enhance the length and compressive stress tries to decrease the length.
Longitudinal Stress Formula
Longitudinal Stress = Force applied / area of the surface
=> Longitudinal Stress= F/A
Tangential or Shearing Stress
when two equal and opposite deforming forces are applied parallel to the cross-sectional area of a cylinder-like object, then there is a relative displacement between the opposite faces of the cylinder.
In this case, the restoring force per unit area due to the applied tangential force is called tangential or shearing stress.
Shearing Stress Formula | Tangential Stress Formula
Shearing stress = Restoring force per unit area
=> Shearing stress= F/A.
Related Post: Mechanical Properties of Solids
A solid body (say sphere) placed in a fluid under high pressure is compressed uniformly on all sides. The force applied by the fluid acts in a perpendicular direction at each point of the surface of the solid body.
This is called Hydraulic Compression and this leads to a decrease in the volume of the solid.
As a result, an internal restoring force is developed inside the solid body.
The internal restoring force per unit area of the body is called Hydraulic Stress.
Hydraulic Stress formula
Hydraulic stress = Internal restoring force per unit area
=>Hydraulic stress = F/A
=>Hydraulic stress = hydraulic pressure