Hooke's Law Principle

Hooke’s Law is the first example of an explanation of elasticity – which is the property of an object or material to be restored to its original shape after distortion.

This ability to return to a normal shape after experiencing distortion can be referred to as a restoring force. Understood in terms of Hooke’s Law, this restoring force is generally proportional to the amount of stretch experienced.

Hooke’s Law states that the force or load applied to a spring is proportional to its extension. In other words, F = - kx, whereas F [N] is the force applied to the spring, k [N/m] is the spring rate or spring constant and x [m] is the extension. The law is named after 17th century British physicist Robert Hooke, who sought to demonstrate the relationship

On the other hand, it is an accurate approximation for most solid bodies, as long as the forces and deformations are small enough. For this reason, Hooke’s law is extensively used in all branches of science and engineering, and is the foundation of many disciplines such as seismology, molecular mechanics and acoustics. It is also the fundamental principle behind the spring scale, the manometer and the balance wheel of the mechanical clock.

Another interesting fact about Hooke’s Law is that it is a perfect example of the first law of thermodynamics. Any spring when compressed almost perfectly conserves the energy applied to it. The only energy is lost due to natural friction.

In addition, Hooke’s law contains within it a wavelike periodic function. A spring released from a deformed position will return to its original position with a proportional force repeatedly in a periodic function.

Hooke’s law may also be expressed in terms of stress and strain. Stress is the force on unit areas within a material that develops as a result of the externally applied force. Strain is the relative deformation produced by stress. However, Hooke’s law is only valid until the elastic limit is

For one, it comes in so many varieties – the compression spring, the extension spring, the coil spring, etc. It is also used to store mechanical energy, the applications are extensive, making possible such things as an automotive suspension system, pendulum clocks, watches and many others.

One real life application where springs are indispensable is the suspension of cars. The oldest type is a leaf spring and still used nowadays. The topmost and longest strip, the master leaf, is curled at each end into an eye by which it is connected to the frame. The leaves below are progressively shorter and less curved, which gives a smoother ride than a plain single leaf could.

Another type of car springs, the coil spring, is simply a spiral of resilient steel rod. It extends as the wheel moves down and compresses as the wheel moves up, so the car body remains at the same level.

The torsion bar is not so widely used but still has its field of applications. Basically it is a spring steel with one end rigidly fixed to the frame. The bar twists as the other end rotates with movements of the suspension lower