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Question
Five resistors, each 3 Ω, are connected as shown in Fig. Calculate the resistance
- between the points P and Q.
- between the points X and Y.
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Solution
r1 and r2 are in series
∴ R1 = r1 + r2
= 3 + 3
= 6 Ω
Now R1 and r3 are in parallel
∴ `1/"R"_"p" = 1/"R"_1 + 1/"R"_3`
= `1/6 + 1/3`
= `(1 + 2)/6`
= `1/2`
- Resistance between P and Q = Rp = 2 Ω
- Resistance between X and Y r4, Rp and r5 are in series
∴ R = r4 + Rp + r5
R = 3 + 2 + 3
= 8 Ω
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