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Current (Classification) |
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The Electric current may be classified into 3 main classes.
(I) Steady Current
(II) Varying Current
(III) Alternating Current.
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(I) Steady Current : When
the magnitude of current does not change with time ,it is
called a Steady Current See the Fig (a) shows the graph between
steady current and time. Note that value of current remains
the same as the time changes. The current provided by a battery
is almost a steady current.
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Fig (a) |
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(II) Varying Current :
When the magnitude of current changes with time ,it is
called a varying current Fig (b) shows the graph between varying
current and time. Note that value of current varies with time.
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Fig (b) |
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(III) Alternating Current
: An alternating current is one whose magnitude changes
continuously with and direction change periodically. Due to
technical and economical reason, we produce alternating current
that have sine waveform (or cosine waveform) as shown in Fig
(c) it is called alternating current because current flows
in alternate direction in the circuit, i.e. from O to T/2
second (T is the period of the wave) in one direction and
from T/2 to T second in the opposite direction.
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Fig (c) |
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