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Question
Two resistors having resistance 8 Ω and 12 Ω are connected in parallel. Find their equivalent resistance.
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Solution
Let R be the equivalent resistance
∴ `1/"R" = 1/"R"_1 + 1/"R"_2`
`1/"R" = 1/8 + 1/12`
= `(3 +2)/24`
`1/"R" = 5/24`
R = `24/5`
= 4.8 Ω
or R = `("R"_1"R"_2)/("R"_1 + "R"_2)`
= `(8 xx 12)/((8 + 12))`
= 4.8 Ω

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