What is the impulse of the body

Impulse ... A notion quite often used in physics. What is meant by this term? If we ask this question to a common man in the street, in most cases we will get the answer that the impulse of the body is a certain impact (push or blow) on the body, so that it can move in the given direction. In general, a fairly correct explanation.

The impulse of the body is the definition with which we first encounter in school: at the physics lesson we were shown how a small trolley was rolling down an inclined surface and pushed a metal ball off the table. It was then that we reasoned that it can influence the strength and duration of this physical phenomenon. From such observations and inferences many years ago, the notion of a body momentum was born as a characteristic of motion, directly dependent on the speed and mass of the object.

The term itself in science was introduced by the Frenchman Rene Descartes. It happened in the beginning of the XVII century. The scientist explained the impulse of the body only as "the amount of movement". As Descartes himself said, if one moving body collides with another, it loses as much of its energy as it gives to another object. The potential of the body, according to the physicist, did not disappear anywhere, but was only transferred from one subject to another.

The main characteristic of a body impulse is its direction. In other words, it is a vector quantity. This implies the following statement that every body in motion has a certain momentum.

The formula for the effect of one object on another: p = mv, where v is the velocity of the body (vector value), m is the mass of the body.

However, the momentum of the body is not the only quantity that determines the movement. Why do some bodies, unlike others, not lose it for a long time?

The answer to this question was the emergence of yet another concept - the momentum of the force, which determines the magnitude and duration of the impact on the object. It is he who allows us to determine how the impulse of the body changes over a certain period of time. The force impulse is a product of the magnitude of the effect (the force itself) on the duration of its application (time).

One of the most notable features of IT is its preservation in an unchanged form provided a closed system. In other words, in the absence of other effects on two subjects, the momentum of the body between them will remain stable for as long as desired. The principle of conservation can also be taken into account in the situation when the external action on the object is present, but its vector effect is 0. Also, the impulse will not change even if the effect of these forces is insignificant or acts on the body for a very short period of time (as, for example, Shot).

It is this law of conservation not for one hundred years that gives the inventors a headache over the creation of the notorious "perpetuum mobile", since it is the basis of such a notion as jet propulsion.

As for the application of knowledge about such a phenomenon as the impulse of the body, they are used in the development of missiles, weapons and new, albeit not eternal, mechanisms.