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Question
Using the concept of force between two infinitely long parallel current carrying conductors, define one ampere of current.
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Solution
One ampere of current can be defined as the amount of current which when flowing (in same direction) through two infinitely long parallel wires separated by one metre produces an attractive force of 2 × 10−7 N/m. The wires must have negligible circular cross-section and they must be placed in vacuum.
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