1)if a bar magnet is fallin thr a loop of wire,the induced current in the loop of wire sets up a field which exerts a force and the loop will be attractive when....

a)the magnet entrs the loop

b)the magnet is halfway through

c)alwaya attraction

d)the magnet is leavin the loop

xplain.....plz wid ans

When a bar magnet falls through a loop of wire, it induces a current in the wire due to the changing magnetic field. This induced current creates its own magnetic field, which interacts with the magnetic field of the falling magnet. The question asks when the loop will experience an attractive force towards the magnet. The correct answer is **a) the magnet enters the loop**. Let’s break this down further to understand why.

The Basics of Electromagnetic Induction

According to Faraday's Law of Electromagnetic Induction, a changing magnetic field within a closed loop induces an electromotive force (EMF), which leads to an electric current. This phenomenon is crucial in understanding how the loop reacts to the magnet's movement.

Understanding the Interaction

As the bar magnet approaches the loop, the magnetic field around the magnet changes. This change induces a current in the wire loop. The direction of the induced current is determined by Lenz's Law, which states that the induced current will flow in such a way as to oppose the change that produced it.

Analyzing Each Scenario

• When the magnet enters the loop: As the north pole of the magnet approaches the loop, the induced current flows in a direction that creates a north pole on the side of the loop facing the magnet. Since like poles repel and opposite poles attract, the loop will experience an attractive force towards the magnet.
• When the magnet is halfway through: At this point, the magnet's influence is still strong, but the induced current may start to decrease as the magnet is no longer changing the magnetic field as dramatically. The attraction may still be present, but it is not as strong as when the magnet first enters.
• Always attraction: This statement is misleading. The interaction depends on the relative position of the magnet and the loop. The attraction is not constant throughout the magnet's journey through the loop.
• When the magnet is leaving the loop: As the magnet exits, the induced current will reverse direction, creating a magnetic field that now opposes the magnet's motion. This results in a repulsive force, pushing the magnet away from the loop.

Conclusion

In summary, the loop will experience an attractive force when the magnet is entering it, as the induced current creates a magnetic field that attracts the magnet. Understanding these principles of electromagnetism helps clarify how magnetic fields interact with conductive materials.