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Potential Method

Kirchhoff's voltage law

Start at point a walk clockwise around the circuit until back at a,

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27-5 Other Single-Loop Circuits

Extend the simple circuit of Fig. 27-3 in two ways

1. Internal Resistance

FIG.27-4 (a) A single loop circuit containing a real

battery having internal resistance r emf ε

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2. Resistances in Series

FIG.27-4 (b) The same circuit spread out in a linethe potentials encountered in traversing the circuit clockwise from a are also shown Va arbitrarilyassigned zero other potentials in the circuit graphed relative to Va'

FIG.27-5 (a) Three resistors connected in series between points a b.

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FIG.27-5 (b) An equivalent circuit with the three resistors replaced with their equivalent resistance Req.

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