Magnet and Iron Nails – Rankers Physics

Bar Magnet: Practice Problem & Solution

Assertion (A): When a magnet is brought near iron nails, only translatory force act on it. Reason (R): The field due to a magnet is generally uniform.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Bar Magnet. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A): A magnet attracts iron nails, causing a translatory force. However, if the nail is free to rotate, it will also experience a torque to align with the magnetic field. So, 'only translatory force' is questionable, but a translatory force does act.

Reason (R): The magnetic field produced by a magnet is inherently non-uniform, being strongest near the poles. Therefore, (R) is false. Thus, (A) is true (considering the translatory attraction) but (R) is false.

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