Question

On the basis of the given circuit arrangement, answer the following questions:

1. What happens to the rod AB when the key K is closed and why?
2. Name and state the rule that determines this behaviour of the rod AB in the above situation.

Answer 1

1. When the key K is closed, the rod AB experiences a force and gets displaced (moves). This happens because a current-carrying conductor placed in a magnetic field experiences a mechanical force.
2. The rule is Fleming’s left-hand rule. Stretch the thumb, forefinger and middle finger of your left hand such that they are mutually perpendicular. If the first finger points in the direction of the magnetic field and the second finger in the direction of the current, then the thumb will point in the direction of motion or the force acting on the conductor.