A bar magnet is dropped vertically, North-pole downwards, such that it passes through a fixed horizontal copper ring. Let a₁ be the acceleration of the magnet when it is just above the ring and a₂ be its acceleration when it is just below the ring. Which of the following relationships is correct? (Neglect air resistance and assume g is the acceleration due to gravity)

Step-by-step solution

When the magnet is falling above the ring, its North pole approaches the ring. According to Lenz's law, the induced current in the ring will flow in a direction that opposes this approach by creating a North polarity on its upper face. This results in an upward repulsive force on the magnet, making its net downward acceleration a₁ When the magnet has passed through and is just below the ring, its South pole is moving away from the ring downwards. The induced current will now flow to oppose this separation by creati