Kinetic energy - a basis of all movement in the nature. With kinetic energy bullets fly, athletes run and planets move. What does this type of energy differ from the others in and as changes?
Instruction
1. Exclusively moving bodies have kinetic energy. Besides kinetic, in mechanics there is also a potential energy which possess or the bodies raised over the surface of the planet (they are attracted by gravitation forces), or the bodies which underwent deformation (elastic spring, a piece of rubber).
2. Kinetic and potential energy is inseparably linked with each other. In the course of falling or flight the body has both the speed, and weight (except for extreme provisions).
3. For determination of value of kinetic energy it is necessary to know the speed of a body (V) and its weight (m). It is possible to use convenient formula E (Kean.) = m * V * V/2. It is read: "Kinetic energy is directly proportional to the work of body weight on a square of its speed, divided into two". From here it becomes clear that at a speed equal to zero, kinetic energy will be also equal to zero (because of a "empty" denominator).
4. At free fall of a body the energy passes from potential into kinetic. For an example it is possible to present the cargo suspended at the height of 10 meters weighing 1 kg. On a suspension it is not movably, its potential energy is equal to all energy (total mechanical energy). Having calculated it on formula E (sweat.) = m * g * h (where h - height, g = 9.8 - the acceleration of gravity, a constant), we will receive 98 J.
5. On the law of energy conservation (ZSE, the fundamental law of the nature) the energy from where does not appear and does not disappear anywhere. It just passes from one look into another. We can calculate kinetic energy at the known height, having taken away from the known total mechanical energy of a system, potential, having substituted h height in already known formula. For four meters E (sweat.) = 1 * 4 * 9.8 = 39.2 J. Znachit, E (Kean.) = E (half-N) - E (sweat.) = 58.8 J.
6. Kinetic energy reaches the maximum value at the end of flight (movement) when speed is high, and the potential energy is equal to zero. Then total mechanical energy completely passes into kinetic. At blow there is heat, and all energy of the movement will turn into internal energy of bodies (motion of the molecules).