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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, in parallel.
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Solution
R = 3 ohm for 1 m
For 5 m : R = 3 x 5 = 15 ohm
But Area A is double i.e. 2A and Resistance is inversely proportional to area so Resistance will be half.
R = `15/2` = 7.5 ohm
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