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Question
A particular resistance wire has a resistance of 3 ohm per meter. Find the total resistance of three lengths of this wire each 1.5 m long, joined in parallel.
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Solution
Resistance of 1 m of wire = 3 ohm
Resistance of 1.5 m of wire = 3 × 1.5 = 4.5 Ω
`1/R=1/4.5+1/4.5+1/4.5=3/4.5`
R = 1.5 Ω
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