The magnitude of the force per unit length between two-parallel current-carrying conductors is:

$\overline{)\frac{\mathbf{F}}{\mathbf{l}}{\mathbf{=}}\frac{{\mathbf{\mu}}_{\mathbf{0}}}{\mathbf{2}\mathbf{\pi}}\frac{{\mathbf{I}}_{\mathbf{1}}{\mathbf{I}}_{\mathbf{2}}}{\mathbf{d}}}$

Force, F:

$\overline{){\mathbf{F}}{\mathbf{=}}\frac{{\mathbf{\mu}}_{\mathbf{0}}}{\mathbf{2}\mathbf{\pi}}\frac{{\mathbf{I}}_{\mathbf{1}}{\mathbf{I}}_{\mathbf{2}}\mathbf{l}}{\mathbf{d}}}$

Since the current are in opposite direction, they will repel each other.

Two long, parallel wires are separated by a distance of 0.400 m (fig. E28.29). The currents I_{1} and I_{2} have the directions shown.

(a) Calculate the magnitude of the force exerted by each wire on a 1.20-m length of the other. I s the for attractive or repulsive?

(b) Each current is doubled, so that I1 becomes 10.0 A and I2 becomes 4.00 A. Now what is the magnitude of the force that each wire exerts on a 1.20-m length of the other?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Magnetic Force Between Parallel Currents concept. You can view video lessons to learn Magnetic Force Between Parallel Currents. Or if you need more Magnetic Force Between Parallel Currents practice, you can also practice Magnetic Force Between Parallel Currents practice problems.