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Question
Calculate the equivalent resistance between the points A and B in Fig. if each resistance is 2·0 Ω.
Solution
r1 = r2 = r3 = r4 = 2 Ω
Both r1 and r2 are connected in series in the figure.
Total resistance in series R1 = r1 + r2
= 2 + 2
= 4 Ω
r3 and r4 are in parallel `1/"R" = 1/r_1 + 1/r_2`
= `1/2 + 1/2 = 1`
R2 = 1 Ω
Total resistance R1 + R2 = 4 + 1 = 5 Ω
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