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Fig. 5.8 If V
B
is known to lag quarter of a
of cycle behind V
A
, which of its terminals
first becomes positive after d?
shown. A very common way of indicating the voltages between them
is as shown there, with two-way arrows. Now let us try to relate this
to the waveform graph, Fig. 5.3a, which tells us that the positive
peak of V
B
occurs quarter of a cycle later than the positive peak of
V
A
. The phasor diagram, Fig. 5.6, tells us the same thing in a simpler
way. Suppose that at a certain instant d is at positive peak relative to
c. Then we know that a quarter of a cycle later either e or f will be at
peak positive relative to the other. Whic ...