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Assertion (A): If a… (Class 12 Physics SQP 2026-27, Q16)

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PhysicsCBSE Class 12 · Sample paper, session 2026-27 · 1 mark · Assertion-reason

CBSE Class 12 Physics sample paper 2026-27: question 16

From the official CBSE sample question paper for 2026-27, section A, question 16, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q16 · 1 mark · Assertion-reasonCompetency-basedElectric Charges and Fields

Assertion (A): If a conductor is placed in an external electric field, the electric field inside the conductor becomes infinity in electrostatic equilibrium.

Reason (R): Free electrons inside the conductor rearrange themselves in such a way that the internal electric field is in the same direction as that of the external field.

  1. (A)both Assertion and Reason are true and Reason is the correct explanation of Assertion.
  2. (B)both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
  3. (C)Assertion is true but Reason is false.
  4. (D)both Assertion and Reason are false.

Source: official sample paper from cbseacademic.nic.in (PDF). See it in the full Sample paper 2026-27.

Hints

Open one hint at a time and try again before the next.

Hint 1

What is the electrostatic field inside a conductor?

Hint 2

Does the field of the induced charges add to or cancel the external field?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. In electrostatic equilibrium the field inside a conductor is zero, not infinite, so A is false.

    ½ mark

  2. Free electrons rearrange to produce an internal field opposite to the external field, cancelling it. R says it is in the same direction, so R is false. Option (D).

    ½ mark

Answer: Option (D)

Where the marks are

  • Both statements false: the internal field is zero because induced charges oppose the external field (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Electric Charges and Fields, one at a time, marked against the answer key and marking points.Back to the full paperSample paper 2026-27: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.