Question

Figure below shows a portion of an electric circuit with the currents in ampere and their directions. The magnitude and direction of the current in the portion $PQ$ is:

• A. $0A$
• B. $3A$ from $P$ to $Q$
• C. $4A$ from $Q$ to $P$
• D. $6A$ from $Q$ to $P$

Answer 1

Answer: (D)

$6A$ from $Q$ to $P$

Using Kirchoff's current law, which states that the net current in a junction is zero
the let The magnitude of the current in the portion $PQ$ is $x$ and the direction P to Q.
$x=-3A+1A-2A-8A+4A+2A$
$x=-13A+7A=-6A$
hence,the magnitude of the current in the portion $PQ$ is $6A$ and the direction from $Q$ to $P$.