LIWA

The Human Eye and the Colourful World

CBSE Class 10 · Science · Chapter 10

Past board exam questions

CBSE 2027 sample paper · 5 marks

I. What is meant by accommodation of the human eye? II. What is the near point of a normal eye and what does it signify? III. Name which type of lens is used to correct the defect in which a person cannot see distant objects clearly. IV. Draw a diagram to show how the choice of your lens in (d) helps to see distant objects clearly?

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I. Accommodation is the ability of the eye lens to adjust (change) its focal length, with the help of the ciliary muscles, so as to focus objects at different distances on the retina. II. The near point is the nearest point (about 25 cm for a normal eye) at which an object can be seen distinctly without strain; it signifies the closest distance at which the eye can focus comfortably (the least distance of distinct vision). III. The defect is myopia (short-sightedness); it is corrected with a concave (diverging) lens of suitable power. IV. Diagram: a concave lens placed in front of the eye. Parallel rays from a distant object (at infinity) pass through the concave lens and diverge so that …

CBSE 2027 sample paper · 5 marks

I. What is dispersion of light? II. Which colour of light deviates the least during dispersion through a prism? III. State why the sky appears dark to an astronaut in outer space. IV. Draw a simple labelled diagram to show how white light splits into different colours while passing through a glass prism.

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I. Dispersion is the splitting of white light into its component colours, because light of different colours (wavelengths) bends through different angles on refraction. II. Red light deviates the least (it has the longest wavelength). III. In outer space there is no atmosphere, so there are no particles to scatter sunlight; no scattered light reaches the astronaut's eyes and the sky appears dark. IV. Diagram: a triangular glass prism with a beam of white light falling on one face; the light bends at both faces and comes out of the other face spread into a band of seven colours (spectrum) – red at the top (least deviated) and violet at the bottom (most deviated), in the order VIBGYOR. …

CBSE 2026 board paper · 1 mark

The pair of eye parts responsible for admitting different amount of light in to the eyes is

  1. Iris and pupil
  2. Ciliary muscles and pupil
  3. Retina and Iris
  4. Ciliary muscles and cornea
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Iris and pupil

CBSE 2026 sample paper · 1 mark

Choose the correct option from the below which explains the reason for us to perceive the day sky as blue.

  1. As sunlight passes through the atmosphere, shorter wavelengths, such as blue are scattered more than other colors.
  2. The sky appears blue because all colors are scattered equally, but blue light is stronger and more visible to the human eye.
  3. The blue color of the sky is due to longer wavelengths like red and orange scattering more than shorter wavelengths, making blue stand out more.
  4. The atmosphere contains blue-colored particles that give the sky its blue appearance.
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As sunlight passes through the atmosphere, shorter wavelengths, such as blue are scattered more than other colors.

CBSE 2026 board paper · 1 mark

When you look at an object very close to your eyes, the :

  1. Ciliary muscles of your eye contract and the eye lens becomes thick.
  2. Ciliary muscles of your eye get relaxed and the eye lens becomes thick.
  3. Ciliary muscles of your eye contract and the eye lens becomes thin.
  4. Ciliary muscles of your eye get relaxed and the eye lens becomes thin.
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Ciliary muscles of your eye contract and the eye lens becomes thick.

CBSE 2026 board paper · 1 mark

A thin beam of white light falls on a face of a glass prism and a spectrum is obtained on a screen. Which of the following options is the correct sequence of colours from top to bottom on the screen ?

  1. Red, Green, Yellow, Violet, Blue
  2. Red, Yellow, Green, Blue, Violet
  3. Violet, Blue, Green, Yellow, Red
  4. Violet, Red, Green, Yellow, Blue
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Red, Yellow, Green, Blue, Violet

CBSE 2026 board paper · 1 mark

Observe the ray diagram described below showing refraction through a prism and choose the correct option for colour of rays 1 and 2 : [Ray diagram: a ray of white light falls on face AB of a triangular glass prism ABC (apex A at the top, base BC at the bottom) and splits inside the prism. Two rays emerge from face AC: ray 1, the upper one, is bent less towards the base BC; ray 2, below it, is bent more towards the base BC.] (Colour of ray 1 — Colour of ray 2)

  1. Blue — Red
  2. Green — Yellow
  3. Red — Violet
  4. Violet — Red
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Red — Violet

CBSE 2026 board paper · 1 mark

Vision defect far-sightedness is found in the eye defects named as :

  1. Myopia and cataract
  2. Myopia and hypermetropia
  3. Presbyopia and hypermetropia
  4. Presbyopia and myopia
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Presbyopia and hypermetropia