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Question
State and define Ohm’s law.
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Solution
Ohm’s law states that at a constant temperature, the current flowing in a conductor is directly proportional to the potential difference across its ends, i.e., if the potential difference is halved, the current is also halved and if p.d. is doubled, the current is also doubled, i.e.,
V (potential difference) ∝ i (current)
Or V = iR, where R is constant, called the resistance of the conductor.
So V = iR represents Ohm’s law.
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