# The dynamics and the concept of strength

**The dynamics and the concept of strength**.

The dynamic, in physics, is that part of classical mechanics that studies the movement of bodies in accordance with the concept of material points seen in the previous article focusing on research into the causes that produce the same movement.

The **classical mechanics** is based on conjecture and fundamentals very close to “common sense”, for this reason it is not very likely to describe phenomena whose speed is close to that of light (∼ 300’000 km/s) or the phenomena related to the micro-cosmos (nuclei, atoms, particles,..), as regards the first case you need of Relativistic Physics, While in the latter it should be resorting to quantum mechanics.

The essential principles on which is based the classical mechanics (or Newtonian physics) are as follows:

- Euclidean space, isotropic and homogeneous
- homogeneous time
- description of physical phenomena on the basis of a reference system
- the principle of conservation
- the principle of least action

A first milestone for the dynamic is the concept of strength.

An object initially unplanned starts moving alone, to move it to a point it is necessary to apply a force.

The concepts of force in the common mentality are especially physical effort, in fact we can think of moving a piece of iron with a calamity or dropping a rock through the window (in the latter case is a force easily observable, the force of gravity).

Keep this article about the dynamics and the concept of strength with a **definition** more general than the latter.

For **strength** means a vector magnitude that is shown in the interaction of two or more bodies, whose specific quality is to induce a change of bikes and generate a deformation.

However, remember that not always force the cover will move, This is because two forces balance.