104 Practical MATLAB® Applications for Engineers
State and analyze the transient solution for the parallel and series resistor capacitor
network (RLC)
Defi ne the system loop and node equations
Use node and loop equations to solve circuit problems
Defi ne and use the superposition theorem when dealing with multiple sources
Recognize that an independent voltage source set to zero is equivalent to a short
circuit
Recognize that an independent current source set to zero is equivalent to an open
circuit
Recognize that a voltage source can be transformed into an equivalent current
source and vice versa
Defi ne and determine the Thevenin’s equivalent circuit of an electrical network
Recognize that the Thevenin’s equivalent circuit can be evaluated for any load of
interest
Defi ne and determine the Norton’s equivalent circuit given an electrical network
Recognize that the relation between Thevenin’s and Norton’s equivalent circuits
consist of a simple source transformation
Use MATLAB® as a tool in the analysis of electric circuits2.3 Background
R.2.1 The idea that matter is composed of atoms is an old concept that was fi rst proposed
by the Greek philosophers Empedocles and Democritus around 500 and 400 BC.
R.2.2 The scientifi c community accepted the existence of the atom in modern times, ini-
tially proposed by the chemist Dalton in the nineteenth century, and supported
and consolidated by Cannizzaro 50 years later.
R.2.3 A n atom i s too sma l l to be seen d i rect ly or even w it h t he help of moder n a nd soph i s-
ticated devices such as a microscope, because its diameter is estimated to be in the
order of 10−^10 m.
R.2.4 Atoms are composed of protons, neutrons, and electrons.
R.2.5 In modern times, J. J. Thomson, around 1897, is credited with the discovery and
study of the electron.
R.2.6 The mass of a neutron is slightly larger than the mass of a proton, and the mass of
an electron is much smaller than either of them.
R.2.7 An electron constitutes the unit of a negative electric charge.
R.2.8 A proton constitutes the unit of a positive electric charge.
R.2.9 Atoms move in nature in a perfectly random way.
R.2.10 The effect of an electron exactly cancels the effect of a proton.
R.2.11 An atom contains a certain number of protons in a nucleus and an equal number of
electrons orbiting the nucleus.
R.2.12 Most bodies in nature are electrically neutral, because they contain equal amounts
of positive and negative charges that exactly cancel one another.