A magnetic field is produced around and within the solenoid. The magnetic field within the solenoid is uniform and parallel to the axis of solenoid. Fm=q(v×B)=Bqv‌sin‌θ Since, angle between v and B=0∘, therefore Fm=0. Now, ‌‌W=F×d‌cos‌φ Since, ‌‌F=0⇒W=0