The student will apply the ohm laws and the laws of Kirchhoff for voltages and currents, to the analysis of electric circuits, so that when concluding the practice, this in possibilities of to check and to corroborate the calculations obtained by means of technical and methods already established, like they are the following ones:
Law of voltage Kirchhoff, in a series ofmeshes.
Law of current Kirchhoff, in a series of nodes.
List of materials and equipment
• A Digital Multimeter.
• 2 variable voltage source.
• 2 ( resistors to 330 ½ w.
• 2 ( resistors to 470 ½ w.
• 2 ( resistors to 560 ½ w.
• Wire connection to the breadboard.
Our development in Kirchhoff's lawsdoes not include rigorous testing, only consider the basic context for understanding circuit theory. Two basic laws for the analysis of circuits containing elements of resistive, inductive and capacitive, are nominated by the German physicist Gustav Kirchhoff (1824 - 1887) the so called "Kirchhoff Current Law (KCL)" and the "Law Kirchhoff's voltage (KVL)."
The Kirchhoff's current law statesthat:
"The sum of the currents that affect a node are zero”
The Kirchhoff's voltage law states that:
"The algebraic sum of voltages around any closed path in a circuit is zero at all times."
Provided by closed, the journey through a series of nodes that end at the starting node without passing through any node more than once. Often called a closed path or loop the loop.
For exampleconsider the circuit shown in Figure 2. is a circuit consisting of two closed paths.
Biography (Gustav Kirchhoff)
(Königsberg, Russia, 1824 - Berlin, 1887) German physicist. Close associate of the chemist Robert Bunsen, spectrographic analysis methods applied (based on the analysis of the radiation emitted by an excited energy body) to determine the composition of the Sun.
In 1845 heenunciated the so-called Kirchhoff's laws applicable to the calculation of voltage, current and resistance in the other in an electrical grid, understood as an extension of the law of conservation of energy, on the theory of the physicist Georg Simon Ohm, as tension which causes the passage of an electric current is proportional to the intensity of the current.
In 1847 he served as Privatdozent(lecturer-employed) at the University of Berlin, and after three years he accepted the post of professor of physics at the University of Breslau.
In 1854 he was appointed professor at the University of Heidelberg, where he met Bunsen. Thanks to the collaboration between the two scientists developed the first techniques of spectrographic analysis, which led to the discovery of two new elements,cesium (1860) and rubidium (1861).
In an attempt to determine the composition of the Sun, Kirchhoff found that when light passes through a gas, it absorbs the wavelengths that emit in the case of preheated.Successfully applied this principle to explain the many dark lines that appear in the solar spectrum, known as Fraunhofer lines. This discovery marked the beginning of a new era in astronomy.In 1875 he was appointed professor of mathematical physics at the University of Berlin.
Content published several scientific works, among which include Vorlesungen über Mathematische Physik (1876-1994) and Gessamelte Abhandlungen (1882, supplement, 1891).
Kirchoff's First Law
In an electrical circuit, it is common to generate power nodes. A node is the circuit where they join more than oneterminal of an electrical component. If you want to rule "node" and think "knot" because that is the reality: two or more components are tied together with each other (actually welded together). Figure 1 shows the most basic of circuits DC (direct current) that contains two nodes.
Fig.1 Basic circuit with two nodes
Note that these are two 1Kohms resistors (R1 and R2) connected on a single...