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Question
In the network shown in the following adjacent Figure, calculate the equivalent resistance between the points.
- A and B
- A and C
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Solution
(a) Rs = r1 + r2 + r3
Rs = 2 + 2 + 2
Rs = 6 Ω
`"R"_1` and `"R"_2` are connected in parallel
`1/"R"=1/"R"_"s"+1/"r"_4 = 1/6 + 1/2 = 4/6 " i.e." 2/3`
R = `3/2`
R = 1.5 Ω
(b) `"R"_("s"_1) = "r"_1 + "r"_2`
`"R"_("s"_1)` = 2 + 2 = 4 Ω
`"R"_("s"_2)` = r3 + r4 = 2 + 2 = 4 Ω
`"R"_1` and `"R"_2` are connected in parallel
`1/"R" =1/"R"_("s"_1) + 1/"R"_("s"_2)`
`1/"R" = 1/4 + 1/4`
`1/"R" = 2/4 ~~ 1/2`
R = 2 Ω
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