A straight horizontal wire is stretched along the east–west line and carries a steady current of 10A from west to east. The region is under a uniform horizontal magnetic field of 0.25T directed from south to north.
(a) Identify the direction in which the wire will experience a mechanical force.
(b) Explain your reasoning clearly, mentioning the relative orientations of the magnetic field, current and force.
(c) If the current is reversed in direction while the magnetic field remains unchanged, what will be the new direction of the force? Give reason.