Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: A bar magnet dropped through a metallic cylindrical pipe takes more time to come down compared to a non-magnetic bar with same geometry and mass.
Reason R: For the magnetic bar, Eddy currents are produced in the metallic pipe which oppose the motion of the magnetic bar.
In the light of the above statements, choose the correct answer from the options given below

We need to evaluate the Assertion-Reason pair about a magnet falling through a metallic pipe.

Assertion A: A bar magnet dropped through a metallic cylindrical pipe takes more time to come down compared to a non-magnetic bar with same geometry and mass.

This is TRUE. When a magnet falls through a conducting pipe, the changing magnetic flux through the pipe induces electric currents (eddy currents) in the pipe walls. By Lenz's law, these currents create a magnetic field that opposes the change in flux -- i.e., opposes the motion of the falling magnet. This creates a retarding force on the magnet, slowing it down significantly. A non-magnetic bar of the same mass and geometry does not produce changing magnetic flux, so no eddy currents are induced, and it falls freely under gravity.

Reason R: For the magnetic bar, eddy currents are produced in the metallic pipe which oppose the motion of the magnetic bar.

This is TRUE. The physical mechanism is:

1. The falling magnet creates a changing magnetic flux through any cross-section of the pipe.

2. By Faraday's law, this changing flux induces an EMF in the pipe.

3. Since the pipe is a conductor, the EMF drives circular (eddy) currents in the pipe walls.

4. By Lenz's law, these eddy currents produce a magnetic field that opposes the cause (the falling magnet), creating an upward force on the magnet.

R is the correct and direct explanation of A. The eddy currents and their opposing effect are precisely why the magnet takes more time to fall through the pipe.

The correct answer is Option 2: Both A and R are true and R is the correct explanation of A.