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Question
Calculate the equivalent resistance between A and B in the adjacent diagram.

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Solution
R1 = 3 + 2 = 5 ohm
R2 = 30 W
R3 = 6 + 4 = 10 ohm
`"R"_1 , "R"_2 and "R"_3 `are connected in parallel
`1/"R" = 1/"R"_1 + 1/"R"_2 + 1/"R"_3`
`=1/5+1/30+1/10=10/30`
R = 3 ohm
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