Uniformly varied movement . In nature, movements are observed much more frequently in which the displacements in the same time intervals are different, so the speed varies over time. These movements are called various.
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- 1 Varied rectilinear motion
- 2 Speed in case of varied movement
- 3 Instantaneous speed
- 4 Sources
Varied rectilinear motion
Varied rectilinear movement is called that movement with which the body makes different movements at equal intervals of time .
The movement of trains , planes , automobiles, etc., as a rule, is varied. Therefore, the displacement formula for linear movements does not serve to calculate their displacements, because the speed at different places on the path is different. To calculate the displacements in the event of such a movement, it is necessary to know the speed and it is necessary to know how to calculate and measure it several times.
Speed in case of varied movement
When operating in varied movement , in certain cases, use is made of the so-called average speed , which the body performing a displacement in a time interval , can be obtained by dividing the displacement by time.
In this case, the average speed shows that the displacement that the body made in a given medium in the unit of time is equal. Knowing it allows calculating the displacement, which will only be valid for that sector of the path where that average speed was defined.
Therefore, the speed in question does not allow, generally speaking, to calculate the displacement and coordinates of a moving body at any moment in time. But in spite of everything, in case of varied movement the concept of speed can be used, since the mechanic is a continuous process.
Taking into account that the continuity of movement consists that the coordinates of the body, as well as its speed , cannot vary in jumps, that is, when a body in rectilinear motion and increasing speed moves in a certain section, said body must pass obligatorily for all the intermediate points that are in said section, without omitting any of them and must take all the speed values included in said movement.
Therefore, at each point of the movement path and at each moment of time , the speed of the body had a certain value. The speed that corresponds to the moment of time or to the point of the path that is considered is called instantaneous speed .
Since the average speed in the varied movement is equal to the ratio between its displacement and the time interval during which said displacement was carried out, it allows us to understand the meaning of instantaneous speed, since the speed in uniform rectilinear movement is equal to this .
The instantaneous speed, or the speed at the given point, is equal to the ratio between the sufficiently small displacement in the sector of the path adjacent to said point and the small interval of time during which said displacement is carried out.