kinetic energy - is, by definition, equal to half the mass of the moving body multiplied by the square of the velocity of the body.It - one of the key terms of modern mechanics.Briefly put, it is the energy of motion, or the difference between the total energy and the rest energy.Yet the essence of it is not fully considered in modern science.
kinetic energy (from c. Kinema - movement) of the body in a state of immobility, is zero.Often, this value does not only relate to the mass and velocity.Thus, according to one definition, the kinetic energy - is the work done at a certain speed.It is measured in joules.
kinetic energy of the system - it is the value, which is closely related to the rate of each of its points.
It is considered as in translation and in the rotation.The first case has been explained in detail above, it is - half of the mass of an object multiplied by its velocity squared.A kinetic energy of rotation of the body is represented as the sum of the kinetic energies of each of the elementary volumes of the body.Or the value of the moment of inertia multiplied by the square of angular velocity divided by two.
Suppose there is any solid, which makes motion around a fixed axis passing through it.This object can be divided into small volume elements, each of which has its own elementary mass.Around a fixed axis of the body under consideration makes movements.In addition, each of the elementary volumes corresponding describes a circle of radius.The same angular rate of rotation.And so the kinetic energy of the body - is the sum of the kinetic energies of all its elementary, moving around the axis of the volume.A simplified version of this formula - half the product of the square of the angular velocity and moment of inertia.
In some cases the kinetic energy - the sum and translational and rotational energy.For example, a non-slip sliding down an inclined cylinder line.Moving forward, it performs a translatory motion, however, while it also moves around its axis.
One of the components of the kinetic energy of rotation - this is the moment of inertia, which mentioned and discussed.It depends on the total weight of the body, as well as its distribution in relation to the axis of rotation.What is it?This measure of inertia about an axis so as to measure translational motion of the inertia mass is.This is a very important variable.The moment of inertia is more difficult to bring the body into a state of revolution.The angular velocity characterizes the speed with which the solid moves around its axis.The unit is the rad / s.The angular velocity is the ratio of the rotation angle to the length of time for which the angle of the rotating object passes.
Theorem of kinetic energy can be formulated like this: work force resultant applied to a particular body, equivalent to a change in the kinetic energy of the body.
