It is known as flat to a surface thing somewhat smooth, lacking in reliefs and elevations; an object that has only two dimensions and that contains infinite points and lines; a schematic representation at scale of a territory or a construction; or the position from which someone analyzes a thing or situation.
Inclined, for its part, is a word that derives from the verb tilt (which means moving something away from your position perpendicular to the horizon).
The notion of inclined plane, then, it combines both notions and refers to a plain or area without relief that forms an acute angle with the ground and that, due to these characteristics, makes it easier to lift or lower an object or body.
The concept, in general, allows to name the simple machinery achieved from a flat area capable of achieving an acute angle with respect to the base and that is used to raise a body to a certain height. This helps to require less force to lift the body than if it were to lift it vertically.
In this sense, we can determine that any inclined plane has three clear functions. Thus, in the first place, we have to state that it can be used as a ramp to, in this way, proceed to raise a specific mass reducing the level of effort that must be made to achieve the objective. A clear example of this is when ramps are placed on a truck to proceed to introduce cattle.
Secondly, it must be emphasized that the second clear function that any inclined plane has is to act as a wedge. In this way it can be used both to cut and to tighten or even to separate or open an element. There are several examples that we can use to understand this work of the aforementioned plan, such as when it is used to hold the doors and prevent them from closing.
A knife, a scissors or an ax are also examples of this second mentioned function that we have exposed.
Third and last, it is necessary to determine that any inclined plane can have the task of working as if it were a propeller. In this way, what is achieved is that the rotary movement of an element in question is linear. The propeller of a ship is a perfect example of this, however, it is not the only one that we can emphasize. Thus, it also acts as a screwdriver when placing a screw on a certain surface.
The mathematician Simon Stevin (1548–1620) was the one who first enunciated the laws that determine the behavior of bodies on an inclined plane. It is important to bear in mind that the operation of this simple machine is affected by various forces, as the force of gravity (the weight, which arises from the magnitude of the mass in the vertical direction), the Normal strength (the reaction force that the plane exerts on the body according to Newton’s Third Law) and the friction force (the friction force that exerts resistance with respect to the direction of displacement of the element or object in relation to the surface).