If the direction of the current in a current-carrying wire is reversed in the presence of a magnetic field, the direction of the magnetic force acting on the wire will also be reversed. This is because the magnetic force on a current-carrying wire is determined by the interaction between the magnetic field and the moving charges (electrons) in the wire.

Mathematically, the magnetic force experienced by a current-carrying wire can be calculated using the Lorentz force equation:

F = q * (v x B)

where:

- F is the magnetic force vector

- q is the magnitude of the charge moving in the wire

- v is the velocity vector of the moving charge

- B is the magnetic field vector

When the direction of the current is reversed, the direction of the velocity vector (v) of the moving charges is also reversed. As a result, the cross product (v x B) changes sign, causing the magnetic force vector (F) to change direction.

In simpler terms, reversing the current direction in a wire is equivalent to swapping the roles of the north and south poles of a magnet. If the current is reversed, the magnetic field created by the wire will also reverse, resulting in a reversal of the magnetic force acting on the wire.