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Question
Find the effective resistance in the following circuit diagrams (Fig.):
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Solution
(b) In the given network, the parallel combination of resistors 40 Ω and 120 Ω is connected in series with the 10 Ω and 20 Ω resistors.
:. Resistance in para!! el is:
`1/"R"_"P" = 1/40 + 1/120 = 4/120 = 1/30`
.·. `"R"_"p"` =3Ω
Effective resistance between P and Q is
R = 10 + 30 + 20 = 60 Ω
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