A conducting wire of length and mass m is placed on a horizontal surface with its length along y direction. There exists a uniform magnetic field B along positive x direction. With wire carrying a current I in positive y direc- tion, the least value of force required to move it in x and y directions are `F_(1)` and `F_(2)`. Now the direction of current in the wire is reversed and the value of two forces becomes `F' _(1)` and `F'_( 2)`. Find the ratio of forces `F_(1) : F_(2) : F'_(1) : F'_(2)`

Answer

`1:1:ne:ne` where `ne=(mg-Bil)/(mg+Bil)`