In the circuit shown, the reading of ammeter when switch $S$ is open and when switch $S$ is closed respectively are
A$3\, A$ and $4\, A$
B$4\, A$ and $5\, A$
C$5\, A$ and $6\, A$
D$6\, A$ and $7\, A$
Medium
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B$4\, A$ and $5\, A$
b When switch $S$ is open total current through ammeter.
$i = \frac{{20}}{{(3 + 2)}} = 4\,A$.
When switch is closed $i = \frac{{20}}{{3 + (2||2)}} = 5\,A$.
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