What is the Difference Between Force and Stress?

The main difference between force and stress lies in their definitions and the way they act upon an object. Here are the key differences:

1. Definition: Force is an external push or pull acting on an object, while stress is the internal resistance offered by a material to resist the applied force per unit area.
2. Direction: Force is a vector quantity, meaning it has both magnitude and direction, and can create motion in an object or resist the motion of the object. Stress, on the other hand, is a tensor quantity that represents the internal resistance of a material to deformation.
3. Relationship: Force is the factor causing stress, and stress is the result of the force applied to a material. The relationship between stress and force is given by the formula: Stress = (Force) / (Resisting area).
4. Unit of Measurement: The SI unit of force is the Newton (N) or kg.m/s², while the SI unit for stress is N/m².

In summary, force is an external influence that can create motion or resist motion in an object, while stress is the internal resistance offered by a material to resist the applied force per unit area. Force is the cause of stress, and the relationship between the two is determined by the formula: Stress = (Force) / (Resisting area).

Comparative Table: Force vs Stress

The main difference between force and stress is that force is an external interaction between objects, while stress is an internal measure of the forces within a material. Here is a table summarizing the key differences between force and stress:

Force and stress are related, as force can cause stress within a material. Stress is calculated by dividing the force applied to a material by the area it is applied to (σ = F/A). Strain, which is related to stress, is a measure of the deformation or change in the shape of the material caused by the stress. Analyzing stress and strain helps engineers and researchers understand how materials and structures respond to external forces and can be used to predict their behavior under various conditions.