Archive for May 2013

Ohm-o-Sapiens (evolved again!)

May 4, 2013

funny - science - physics - cruel circuit problem kirchoff lawThe human species is continuously evolving – from the early hominids such as Homo Robustus, through the Neanderthals, and eventually Homo Sapiens. Physics students (Genus: Ohm-o-Sapiens) are clearly a new advancement in the Human species, as shown by the ability to tolerate torment provided by Physics Teachers…

OK, enough jokes – what we are doing with this post is going beyond the prior posts on electric circuit theory, and into component analysis. We have already looked at Ohm’s Law, Kirchoff’s Laws, and Thevenin’s Law – these are all based on the simple concept of simple “ohmic components”. Such circuits are relatively simple to solve (except like ones to left, and this one) – you use the rules of parallel and serial circuit elements to simplify the problem, and solve using Ohm’s Law.

Some components are not that easy – they don’t follow the simple patterns of ohm’s law. These devices do not have a constant resistance for a variety of applied voltages – their characteristic Voltage – Current graphs show a curve, and this is something you must be able to describe, analyse and discuss.