Figure below shows a portion of an electric circuit with the currents in amperes and their directions. The magnitude and direction of the current in the portion $P Q$ is
A
zero
B$3 \,A$ from $P$ to $Q$
C$4 \,A$ from $Q$ to $P$
D$6 \,A$ from $Q$ to $P$
KVPY 2011, Medium
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D$6 \,A$ from $Q$ to $P$
d (d)
Using Kirchhoff's junction rule, directions and magnitudes of currents are as,
Clearly, current in the portion $P Q$ is from $Q$ to $P$ is $6 A$.
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