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The given figure shows image… (Class 10 Science 2026, Q33)

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ScienceCBSE Class 10 · Board exam 2026, set 31/1/1 · 2 marks · Short answer

CBSE Class 10 Science 2026: question 33

Set in the CBSE Class 10 board exam of 2026, paper 31/1/1, section C, question 33, for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q33 · 2 marks · Short answerCompetency-basedLight – Reflection and Refraction

The given figure shows image formation by a lens. Analyse the figure and answer the following questions:

  1. (a)

    What is the type of lens used for image formation in the given ray diagram?

    0 marks
  2. (b)

    If the real image is formed at a distance of 30 cm from the lens and the size of image is twice the size of the object, then where was the object placed?

    0 marks

Figure in the paper: Ray diagram: object AB stands vertically on the principal axis to the left of a lens drawn as a tall rectangle. Image A'B' is formed further left, on the same side as the object, with B' above the axis. Two rays from B are shown: one parallel to the axis refracting through the lens, and one passing through the optical centre; both are drawn as dashed lines extended back to B'. See it in the official paper.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2026 board paper, set 31/1/1.

Hints

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

Hint 1

Which lens can give an enlarged image?

Hint 2

A real image is always inverted, so the magnification is negative.

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. (a) The image is enlarged and erect and forms on the same side as the object, with the refracted rays traced back to meet at B'. Only a converging lens does this, so the lens is a convex (converging) lens.

    1 mark

  2. (b) The image is real and twice the size of the object, so it is inverted: . Also cm. For a lens, .

    ½ mark

  3. cm. The object was placed 15 cm in front of the lens (on the left side).

    ½ mark

Answer: (a) Convex lens; (b) u = −15 cm, i.e. 15 cm in front of the lens

Where the marks are

  • Identifies convex/converging lens (1 mark)
  • Uses m = v/u with m = −2 for a real image (½ mark)
  • u = −15 cm (½ mark)

Revise the chapter

Practise this chapterBoard-style questions from Light – Reflection and Refraction, one at a time, marked against the answer key and marking points.Back to the full paper2026 board paper, set 31/1/1: 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.