Two conducting rails P and Q are held parallel to each other in the plane of the paper. There is uniform magnetic field ‘B’ perpendicular to the length of the rails going into the paper. A metal rod is kept touching both the rails and is perpendicular to the rails. A dc source is connected, with switch K, to the ends of the rails on one side as shown in the figure. Select the correct statement describing the situation of the metal rod when the switch K is closed.

The rod will move along the rails from in the direction from Y to X.

The correct answer is Option (4) → The rod will move along the rails from in the direction from Y to X.

By Fleming’s left hand rule.

Rod will experience force in the direction from Y to X.

Hence (4) is the correct answer.