Power and electromotive force in a didactic alternating current generator

Electric generators are potential topics to be applied in teaching and learning physics. They are the source of all modern technology and are part of everyday life for students. Therefore, in this work, a didactic alternating current electric generator of low cost, was produced, in which it was possible to approach the generation of electric energy and the relationships between electromotive force, power and current in a resistive circuit. Students can experience through practice and graphical analysis the relationship between these quantities in cases where: (i) there is no load connected to the generator, (ii) the generator rotation frequency is kept constant, (iii) the voltage in the terminals of a resistive load is constant and (iv) the case is that a resistance value is fixed and the generator rotation frequency increases. All experimental data agree with the theories of electrical circuits, making this experiment a potential tool for the experimental teaching of electromagnetism.

Keywords
Teaching; Construction; Electric Generator; Electromotive Force; Power