Basic Electrical Circuits
Dr Nagendra Krishnapura
Department of Electrical Engineering
Indian Institute of Technology Madras
Lecture – 01
(Refer Slide Time: 00:15)
Hello and welcome to Basic Electrical Circuits. As the title says, this course is about circuits,
so the first thing we will do is to learn what circuits are all about. I have just put down that
electrical circuits are interconnections of electrical components. Now of course, that does not
explain too much we will get into more details of that, but what happens in electrical circuits
is that there are currents and voltages which are basically some other representations of
charges and fields. So what happens in electrical circuits is that charges move in certain ways
and they move in interesting ways that carry out certain useful functions.
So, unlike a mechanical gadgets in an electrical circuit you do not say any moving parts; all
the actions happens inside the wires and inside the components in the forms of charges
moving and fields taking on some values and somewhere and so on. So there necessarily
more abstract than mechanical gadgets; so for that reason, we have to learn to deal with
abstract quantities such as charge and field and voltage and current and so on. By abstract I
do not meant that their unreal, what I mean is you cannot see or perceive them directly;
whereas, in a mechanical gadget you can see the object moving.
