Task id17069

In the diagram shown in Fig. 30.5, the length of the conductor is l=20 cm, its speed is u=1 m/s and the resistance of the light bulb is R=1 Ohm. A magnetic field with induction B = 0.5 T is excited perpendicular to the plane of the drawing. What force must be applied to the conductor so that it can move at the specified speed?