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Question
You are provided with three resistors of resistance 1.0 Ω, 2.0 Ω and 3.0 Ω How would you connect them to obtain the total effective resistance 1.5 Ω? Draw diagram of the arrangement and check it by calculations.
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Solution
Two resistors of resistance 1.0 Ω and 2.0 Ω are connected in series and then this combination is connected in parallel with the resistor of resistance 3.0 Ω. The arrangement is shown in given figure alongside
Total resistance of series combination R = 1 + 2 = 3 Ω.
Total effective resistance of parallel combination
R = `(3 xx 3)/(3 + 3) = 1.5 Ω`
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