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NEET PHYSICSMAGNETISM AND MATTEREasy

Question

Given below are two statements: Assertion (A): Gauss's law for magnetism states that the net magnetic flux through any closed surface is zero. Reason (R): The magnetic monopoles do not exist. North and South poles occur in pairs, allowing vanishing net magnetic flux through the surface.

A

(A) is True but (R) is False.

B

(A) is False but (R) is True.

C

Both (A) and (R) are True and (R) is the correct explanation of (A).

D

Both (A) and (R) are True but (R) is not the correct explanation of (A).

Step-by-Step Solution

  1. Assertion Analysis: Gauss's law for magnetism is mathematically expressed as BdA=0\oint \mathbf{B} \cdot d\mathbf{A} = 0. This implies that the net magnetic flux passing through any closed surface is always zero. Hence, the assertion is True.
  2. Reason Analysis: The fundamental physical justification for Gauss's law in magnetism is the non-existence of isolated magnetic poles (monopoles). Magnetic field lines always form continuous closed loops; they do not start or end at a point (unlike electric field lines which start/end on charges). Thus, the number of field lines entering a closed surface must equal the number of lines leaving it. Hence, the reason is True.
  3. Link: The fact that magnetic monopoles do not exist is the direct reason why the net flux is zero. Therefore, (R) is the correct explanation of (A).

Exam Context & Concepts Covered

This question aligns with the NEET PHYSICS syllabus, specifically targeting concepts from MAGNETISM AND MATTER. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

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