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Question
A particular resistance wire has a resistance of 3 ohm per meter. Find the potential difference of the battery which gives a current of 2 A in each of the 1.5 m length when connected in the parallel to the battery (assume that resistance of the battery is negligible).
Solution
A current of 2.0 A flows via each of the parallel-connected wires.
Resistance of 1 m wire = 3.0 Ω
Resistance of 1.5 m wire = 3 × 1.5 = 4.5 Ω
I = 2 A
V = IR
= 2 × 4.5
= 9 V
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