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Science (086) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [1] medium exam-ready
Assertion (A): When the current through a straight conductor is reversed, the direction of the magnetic field around it also reverses. Reason (R): The magnetic field around a straight conductor depends on the magnitude but not the direction of the current. (A) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A). (B) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A). (C) Assertion (A) is true, but Reason (R) is false. (D) Assertion (A) is false, but Reason (R) is true.
  1. A Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
  2. B Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
  3. C Assertion (A) is true, but Reason (R) is false.
  4. D Assertion (A) is false, but Reason (R) is true.
Generated by claude-sonnet-4-6 · 2026-06-26 01:10 · grounding rag
Model Answer

(C) Assertion (A) is true, but Reason (R) is false.

The Assertion is true — reversing current reverses the magnetic field (Activity 12.4). The Reason is false — the direction of the magnetic field depends on the direction of current, not just its magnitude (Right-Hand Thumb Rule).

Explanation

The key is that the Reason contradicts the Right-Hand Thumb Rule. The direction of the magnetic field around a straight conductor depends on both magnitude and direction of current. Since the Reason incorrectly states "direction does not matter," it is false, making option (C) correct.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.