The force experienced by a current-carrying conductor placed in a magnetic field is the largest when the angle between the conductor and the magnetic field is:(a) 45°      (b) 60°      (c) 90°      (d) 180°

Explanation

Experiments have shown that the force experienced by a current-carrying conductor or the displacement of the rod is the largest (or the magnitude of the force is the highest) when the angle between the conductor and the magnetic field is  90° (or, the direction of the electric current and magnetic field are perpendicular to each other).