Ampere's law.

В 21 веке, казалось бы, открыты все законы nature. Magnetism, electricity, the molecular and atomic world are an open book. At the same time, many laws, discovered over a hundred years ago, do not lose relevance to this day, being the basis for the work of many familiar objects. First of all, we are talking about electricity. The name of Andre Ampere, the French physicist-inventor, not only gave the name of the physical law, but is also widely known to physicists and schoolchildren around the world thanks to the phenomenon described by him.

In 1820, based on the description of Oerstedthe interaction of the magnetic needle and the current flowing through the wire, Ampere made the most important discovery, which was called the Ampere Law. The wording of it briefly reads as follows:

transmission of electric current in onedirection through two conductors arranged in parallel to each other, leads to their mutual pushing. Passing it in different directions, other things being equal, causes mutual attraction of two conductors.

In addition to these findings visible to the unaided eye, Ampere's Law includes a number of concepts discovered by the same researcher at the same time.

Having drawn a conclusion about the behavior of two conductors withpassing the current through them in different directions, the French scientist began to investigate the forces that ensure their behavior. The logic of his reasoning was simple: an electric current passed through a conductor creates a magnetic field. Figuratively, it can be represented as concentric circles that frame the conductor cross-section. Another conductor, provided that it is parallel to the first and the distance between them is small, falls into the region of the action of the magnetic field, as a result of which a force is produced that acts on the atoms of the conductor and drives them. Ampere's law also allows us to explain the observations that have arisen:

  • The magnetic field is the result of any electrical current flowing;
  • The magnetic field affects the moving electric charges.

Основываясь на проделанном эксперименте и obtained results, André Ampere related forces and phenomena affecting conductors at the time of electric current flow through them, therefore Ampere's Law can be represented by the formula:

F = IBl sin a.

Where F is the Ampère force, i.e. force acting on a conductor with current, located in a magnetic field;

AND - current strength;

l- the length of the conductor;

AT- modulus of the magnetic induction vector;

sin a - the sine of the angle formed between the vector of magnetic induction and the conductor.

The Ampère force is a vector quantity, i.e. having a direction. It can be determined with the help of the so-called "Rules of the left hand":

  • четыре пальца левой руки направлены в сторону direction of the flow of electric current, the vector of magnetic induction (B) thus enters the palm perpendicularly. Then the direction of the current intensity will indicate the thumb, bent in the plane of the palm.

In modern science, the application of the Ampere Law, inmainly, the production of electrical equipment. In particular, we are talking about loudspeakers and speakers. The principle of the loudspeaker, for example, is to convert the electrical energy into an acoustic one. The coil - the basis of any speaker or loudspeaker - passes through itself an alternating current, the frequency of which corresponds to the frequency of the microphone or speaker. As Ampere's Law states, the coil begins to oscillate under the action of a current, oscillations are transmitted parallel to the axis of the loudspeaker of the device's diaphragm. As a result, sound waves are radiated, which we hear.

In addition to creating the Ampere Law, the inventor is known for having left his name in physics for centuries, since it was assigned to a unit of measurement of the current strength.