Question

Two long straight parallel conductors carrying Steady Current i a n i b along the same direction as separated by a distance D how does the one explain the force of attraction between them if a third conductor carrying a current I see the opposite direction is placed just the middle of these conductors when is resultant force acting on a third conductor

Answer 1

I think this will help you

Answer 2

Given: Currents = 2 = A and B

Distance between them = D

To Find: Force between the conductors

Solution:

Magnitude of magnetic field produced by conductor 'a' at the point on conductor b is -

B = uoI/2πd

Based on the direction of current flow in conductor 'a, the direction of the magnetic field will be perpendicular inward / outward to the two conductors' plane.

Thus,

Force per unit length = uoIaIb/ 2πd

Answer: The direction of force experienced by wire a will be towards wire b, thus the force will be attractive.