Ok, a conductor PQ is placed on a U-shaped conducting rails situated in a magnetic field, B directed inside the plane of paper. When it is moved to left with velocity ,v, the free electrons will experience a Lorentz Magnetic Force,
F = qvB where q,v=Charge and velocity of the free elctrons
This force, F will drive free elctrons to point P(as per Fleming's Left Hand Rule) and accumulate same positive charges on point Q
Now the force on the movable arm PQ is given by
F' = ILBsin90 where, I=Induced Current L= Length of Conductor
This force, F' will act to the opposite direction of velocity, v.Hence same amount of external work is needed to be done to move the arm to left(as ler Fleming's Left Hand Rule).
Now, the question is that in general, the force ILBsin(theta) is derivable from the force, qvB and I think both are magnetic Lorentz force. Also, generally, both the forces have same direction.
But here in this case both the forces have different direction. Do both are different.If yes, how?
If both the forces here are same then, how could that be possible?