above diagram seem to indicate additive voltages (from left to right, we see - and + on the 6 volt
source, - and + on the 8 volt source). Even though these polarity markings would normally indicate
an additive effect in a DC circuit (the two voltages working together to produce a greater total voltage),
in this AC circuit they’re actually pushing in opposite directions because one of those voltages
has a phase angle of 0
o and the other a phase angle of 180o
. The result, of course, is a total voltage
of 2 volts.
We could have just as well shown the opposing voltages subtracting in series like this: (Figure
2.14)