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Question
You have three resistors of values 2Ω, 3Ω and 5Ω. How will you join them so that the total resistance is less than 1Ω? Draw diagram and find the total resistance.
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Solution
The three resistors should be connected in parallel
To get a total resistance less than 1Ω
In parallel, if the equivalent resistance is RP, then
`therefore 1/R_p = 1/R_1 + 1/R_2 + 1/R_3`
`therefore 1/R_p =1/2+1/3+1/5`
`therefore 1/R_p = (15+10+6)/30`
`therefore 1/R_p = 31/30`
⇒ `R_p = 30/31 = 0.97 Ω`
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