Question

Why is magnetic force exerted by a small curent carrying element on another smal element in general not equal?

Answer 1

due to eddy current i guess which develops due to the induced emf..

Answer 2

Because charges ordinarily cannot escape a conductor, the magnetic force on charges moving in a conductor is transmitted to the conductor itself. The magnetic field exerts a force on a current-carrying wire in a direction given by the right hand rule 1 (the same direction as that on the individual moving charges).