A conductor ABCDE, shaped as shown, carries current I. It is placed in the x-y plane with the end s A and E on the x-axis. A uniform magnetic field of magnitude B exists in the region, The force acting on it will be

To find the Ampere's force on a conductor of any shape, replace the conductor by an imaginary straight conductor joining the two ends of the given conductor. So, if B is in x-direction, then the imaginary straight conductor will be along the field and the force acting on it will be zero. If B is in y direction, then the force will be $\mathrm{\lambda BI}$ acting along the z direction. Similarly, if B is in the z direction, then the force will be $\mathrm{\lambda BI}$, acting along the negative y direction.