A Flush Toilet Model for the Transistor

• Autores: Giovanni Organtini
• Localización: The Physics Teacher, ISSN 0031-921X, Vol. 50, Nº. 4, 2012, pág. 221
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • In introductory physics textbooks, diodes working principles are usually well described in a relatively simple manner. According to our experience, they are well understood by students. Even when no formal derivation of the physics laws governing the current flow through a diode is given, the use of this device as a check valve is easily accepted. This is not true for transistors. In most textbooks the behavior of a transistor is given without formal explanation. When the amplification is computed, for some reason, students have difficulties in identifying the basic physical mechanisms that give rise to such an effect. In this paper we give a simple and captivating illustration of the working principles of a transistor as an amplifier, tailored to high school students even with almost no background in electronics nor in modern physics. We assume that the target audience is familiar with the idea that a diode works as a check valve for currents. The lecture emphasis is on the illustration of physics principles governing the behavior of a transistor, rather than on a formal description of the processes leading to amplification.