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Question
Calculate the effective resistance across AB?

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Solution
5 Ω and 4Ω are in series

∴ R1 = (5 + 4)Ω = 9Ω

Now, 9Ω and 3Ω are in parallel
`therefore R_2 = (9 xx 3)/(9+3)=9/4Ω`
Now, 2 8Ω and R2 are in series

`therefore R_3 = 8 +9/4 =41/4 Ω= 10.25Ω`
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