Assertion and Reason: Force on Current-Carrying Coil – Rankers Physics

Force Acting on Current Carrying Conductor: Practice Problem & Solution

Assertion (A): A current-carrying coil placed in a uniform magnetic field experiences a force which depends on the orientation of plane of the coil relative to the field direction. Reason (R): A current-carrying conductor placed in a magnetic field experiences a force \( F = I L B sin \theta \).  
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

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Force Acting on Current Carrying Conductor. Understanding the underlying formula is key to arriving at the correct answer below:

A current-carrying coil in a uniform magnetic field experiences a torque \( \tau = NIAB sin \alpha \), where \( \alpha \) is the angle between the area vector and the magnetic field. This torque and the resultant forces clearly depend on the coil's orientation, making (A) true. The force on a segment of a current-carrying conductor is given by \( F = ILB sin \theta \). This fundamental principle explains the origin of the forces acting on the sides of the coil, leading to the overall torque and forces in (A). Both (A) and (R) are true, and (R) is the correct explanation of (A).

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