Introduction to Stress Formula
In physics, stress is a primary scalar quantity. Stress is defined as the acting force on a unit area. When an external force is applied to a material, stress is generated. It is measured as the force per unit area of a material. Stress is denoted by σ. The measuring unit of stress is N/m2 or Pascal. Here, we are going to discuss several stress formulas briefly. Students should learn all the formulas for their exam preparation.
Stress Formula in Details
If the cross-sectional area of the material is A and the applied force is F, the stress can be expressed as-
σ = F/A
Bending Stress Formula
When a large load is applied to a material, bending stress is produced. The bending stress formula is σ = MC/I. Here, M is the bending moment, which is the product of the distance between the point of interest and force. C is the distance from the neutral axis and I is the moment of inertia.
Dimensional Formula of Stress
Every scalar or vector quantity has a particular dimensional formula.
Stress = Force * Area-1
So, the dimensional formula = [M] * [L1T-2]
= [M1L1T-2]
Here, M = mass, L = length, T = time.
[Image will be Uploaded Soon]
Conclusion
Stress is a primary quantity of Physics. Students should learn the stress formula as it has multiple applications in Physics. They should learn the derivation of the formula and the dimensional formula. Also, they can learn the derivation of the dimensional formula to develop a better understanding of the concept of Stress.
FAQs on Stress Formula
1. Define Various Types of Stress.
Ans: In physics, there are mainly two types of stress- normal stress and tangential stress. Normal stress is of two types, that are longitudinal stress and volume stress. Longitudinal stress is of two types- tensile stress and compressive stress. When the deforming force is perpendicular to the cross-sectional area, normal stress is produced. When the deforming force acts along the length of the body, it is called longitudinal stress. Tensile stress increases and compressive stress decreases the object’s length. When the applied force acts from all dimensions of the object, it is called bulk stress or volume stress. When the applied force is parallel with the cross-sectional area, tangential stress is produced.
2. Derive the Dimensional Formula of Stress.
Ans: In physics, every scalar and vector quantity has a dimensional formula. The dimensional formula is derived from the main formula of the quantity. Stress is a scalar quantity in physics. The formula of stress is expressed as, σ = F/A, where F is the applied force and A is the cross-sectional area.
Now, stress = Force * Area-1
Dimensional Formula = [M] * M0[L1T-2]
= [M1L1T -2]
Where M is the mass, L is the length and T is the time. M, L, and T are the primary quantity for measuring the dimensional formula of any quantity in physics. Thus, we can derive dimensional formulas of any scalar or vector quantity.
3. Explain Bending Stress and its Formula.
Ans: Stress is the externally applied force on the material per unit area. Bending stress is a special type of stress. When the force of a large load is applied to a body, bending force is produced. The force of the load is pointed to the moment of inertia of the body. Two points of the side of the body remain the same and the moment of inertia goes down. The bending stress is calculated by the bending moment, the moment of inertia, and the distance from the neutral axis. The bending stress, σ = MC/I, where M is the bending moment, C is the distance from the neutral axis, and I is the moment of inertia.
