Page 173 - Basic Electrical Engineering

Applying Norton’s theorem, let us calculate the current that would flow
through the load resistance, R = 5 Ω as in Fig. 2.74. The first step is to
L
remove the load resistance and then short circuit the terminals AB as shown
in Fig. 2.75, and calculate I . This is done as follows.
SC
By observation we see that when terminals A and B are shorted, terminals
C and D also get shorted. Two 4 Ω resistances get connected in parallel

across terminals EF, their equivalent resistance become 2 Ω. Thus the total
current, I supplied by the battery becomes

Figure 2.75