For the love of physics walter lewin may 16, 2011 duration. Equation 1 in the diagaram expresses an external voltage v y. The latter is com parable with a trimmer where multiple turns of a screwdriver are used to rotate a worm gear that rotates a wiper between opposite ends of a circular track. They are not usually accessible by the end user of the equipment, and their setting may be sealed or fixed when the equipment is assembled. A is more suitable for graph containing denpendent source. Pdf thevenins theorem and its applications researchgate. The voltage at the terminals is calculated for an injection of a 1amp test current at the terminals.
A few examples are presented after this page to illustrate the use of thevenins theorem. Lutilisation des seules lois des mailles et des noeuds nous. As originally stated in terms of dc resistive circuits only, thevenins theorem aka helmholtzthevenin theorem holds that. Thevenins resistance is the ratio of this source voltage to its current, as marked in fig.
Circuit pneumatique cours et exercices, exercice et corrige circuit electrique ofppt, td pneumatique mei, des. Thevenin s example summary 1 the graph shown in the right hand side gives the final result for thevenin s theory. Aug 21, 20 the thevenin theorem explains how to simplify a complex circuit. The thevenin theorem explains how to simplify a complex circuit. Thevenins example summary 1 the graph shown in the right hand side gives the final result for thevenins theory. This is equivalent to calculating the thevenin resistance. Thevenins equivalent circuit of an open circuit voltage, thevenin voltage, v th and the total resistance from the open terminals side, thevenins equivalent resistance, r th. A fullsize, gheoreme potentiometer is shown in figure this system wastes far theoreke power than if the potentiometer controlled the lighting or heating element directly as a rheostat. R th is the input or equivalent resistance at the terminals when the sources are turned off. Sometimes a picture says more than thousand words, so here are two pictures to explain what thevenins theorem is about.
This can be used to powerup associated components for example, an audio amplifier. Permission is granted to copy, distribute andor modify this document under the terms of the gnu free documentation license, version 1. Any twoterminal network consisting of resistors, fixed voltagecurrent sources and linear dependent sources is externally equivalent to a circuit. In circuit theory, thevenins theorem for linear electrical networks states that any combination of voltage sources, current sources, and resistors with two terminals is electrically equivalent to a single voltage source v in series with a single series resistor r. Pdf thevenins theorem and its applications find, read and cite all the. This voltage divided by the 1 a current is the norton impedance r no. Any linear electrical network containing only voltage sources, current sources and resistances can be replaced at terminals ab by an equivalent combination of a voltage source v th in a series connection with a resistance r th.