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Question
A uniform wire with a resistance of 27 Ω is divided into three equal pieces and then they are joined in parallel. Find the equivalent resistance of the parallel combination.
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Solution
When a wire of uniform thickness with a resistance 27 Ω is cut into three equal pieces, the resistance of each piece = `27 /3` = 9 Ω.
Now, the equivalent resistance of three 9 Ω resistors connected in parallel is:
RP = `[1/9 + 1/9 + 1/9]^-1`
= 3 Ω
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