Flux density, B, near conductor 2 due to I₁ is given by

So, the force which acts on length   of conductor 2 is given by

Therefore, the force per unit length is given by

Also, by Newton’s third law we can say that there is an equal but opposite force acting on conductor 1.

Now, if F/ .= 2 × 10^-7 Nm^-1 and r = 1m and I₁ = I₂, then the current in each conductor is 1 Amp.

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