Question

 Two straight, parallel, current-carrying wires separated by a distance of 5cm contain the same 1000 A current, flowing in similar directions. Determine the force per unit length exerted by the two wires.

Answer 1

We have given that,

$I_1=I_2 = 1000A$

$r = 5cm = 0.05m$

We know the formula,

$\dfrac{F}{l} = \dfrac{\mu_0I_1I_2}{2\pi r}$ $= \dfrac{4\pi \times 10^{-7}\times1000 \times 1000 }{2 \times 3.14 \times0.05} = 4Nm^{-1}$