As follows from the energy conservation law, any body always has energy.In the presence of motion is clear: there is a speed or acceleration, which, combined with the weight, gives the desired result.However, when the body is at rest, it is, paradoxically, can also be characterized as having energy.
Thus, the kinetic energy produced by the motion, the potential - with the cooperation of several bodies.If the first is more or less obvious, it is often the force that occurs between two fixed objects, is beyond comprehension.
well known that the Earth affects all of the body, which are on the surface due to the gravitational field.That is, it attracts any object with a certain force.If you move the object, changing its height, there are also changes in the energy index.Just when lifting body has acceleration.However, in its highest point, when the object (even for a split second) is fixed, it has the potential energy.The fact is that it is still drawn to the field of the Earth itself, which required the body reacts.
In other words, there is always the potential energy due to the interaction of several objects constituting the system, regardless of the size of the objects themselves.At the same time the default one represented our planet.
potential energy - the value of which depends on the mass of the object and the height to which it is raised.International designation - letters Ep.The formula of the potential energy is as follows:
Ep = mgh,
where m - mass, g - gravitational acceleration, h - height.
important to consider in more detail the parameter of height, since it often causes difficulties in solving problems and understanding the value of the quantity.The fact that any vertical movement of the body has a start and end point.For the correct location of the potential energy of interaction of bodies is important to know the initial height.If not specified, its value is zero, that is the same as the Earth's surface.In the case, if the starting point is known as the reference, and the final height, it is necessary to find the difference between them.The resulting number will be sought, and h.
It is also important to note that the potential energy of the system can have a negative value.Suppose that we have already raised above the body of the Earth, therefore, it has a height which is called primary.When he lowered the formula would look like this:
Ep = mh (h2-h1).
Obviously, the greater h1 h2, therefore, the value is negative, the entire formula and give a minus sign.
curious that the potential energy of the higher, the farther from the Earth's surface located body.To better understand this fact, we think about it: the higher the need to raise the body above the Earth, the thoroughly perfect job.The higher the value of the work of any force, so to speak, it invested more than energy.The potential energy, in other words - it is the energy possibilities.
Similarly, you can measure the energy of interaction of bodies under tension subject.
The topic under consideration is necessary to separately discuss the interaction of charged particles and electric field.In such a system will be present potential energy of the charge.Consider this fact more.On any charge that is within the electric field of the same name operating power.Moving particles is due to the work done by this force.Given that the actual charge and the electromagnetic field (more precisely, the body created it) - it is a system, we also get the potential energy of movement of charge within a given field.Since this form of energy - is a special case, he was awarded the title of electrostatic.
