Current is the rate of change of current passing throught a point each second. 1 ampere is defined as the current in two infinitely long straight wires 1m apart in a vacuum which produces a force of 2E-7 N/m on each wire.(adsbygoogle = window.adsbygoogle || []).push({});

My question is why we choose current as base unit rather than charge?

and why the force needed is 2E-7 N/m but not 1N/m?

Thx

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# Coulomb and ampere

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