Uniform and uneven movement are the most important concepts of kinematics. The main point of this section of physics is that, considering the translational motion of a body, it should be borne in mind that all its points move in the same direction with exactly the same speed. That is why it is not necessary to characterize the movement of the entire given body; one can limit oneself to only one point of it.
The main characteristics of any movement include its trajectory, movement and speed. A trajectory is just a line existing only in the imagination along which a given material point moves in space. Displacement is a vector directed from the starting point to the ending. Finally, speed is a general indicator of the point's movement, which characterizes not only its direction, but also the speed of movement relative to any body, taken as a reference point.
Uniform rectilinear movement is in many ways an imaginary concept, which is characterized by two main factors - uniformity and straightness.
The uniformity of movement means that it is carried out at a constant speed without any acceleration. The straightness of the movement implies that it occurs along a straight line, that is, its path is an absolutely straight line.
Based on all of the above, it can be concluded that uniform rectilinear motion is a special type of motion, as a result of which the body performs the same movement for absolutely equal time intervals. So, dividing a certain interval into equal intervals (for example, one second), it will be possible to see that with the above movement the body will travel the same distance for each of these segments.
The speed of uniform rectilinear motion is a vector quantity, which in numerical terms is equal to the ratio of the path traveled by the body over a given period of time to the numerical value of this interval. This value does not depend on time in any way; moreover, it is worth noting that the speed of uniform rectilinear motion at any point on the trajectory absolutely coincides with the movement of the body. In this case, the quantitative value of the average velocity for an arbitrary period of time taken is equal to the instantaneous velocity.
Uniform rectilinear movement is characterized by a special approach to the path that the body travels over a certain period of time. The distance traveled with this type of movement is nothing more than a displacement module. The movement, in turn, is a product of the speed with which the body moved, for the time during which this movement was carried out.
It is natural that if the displacement vector coincides with the positive direction of the abscissa axis, then the projection of the calculated velocity will not only be positive, but also coincide with the magnitude of the velocity.
Uniform rectilinear motion can be represented, including, and in the form of an equation in which the relationship between the coordinates of the body and time will be reflected.