Xam Idea Class 10 Science Chapter 11 Solutions: The Human Eye And The Colourful World

Xam Idea Class 10 Science Solutions for Chapter 11 – The Human Eye And The Colourful World helps you to understand all the basic concepts about your eye. These solutions are prepared by our subject matter experts as per the latest CBSE syllabus for Xam Idea Class 10 Science Solutions. We have included detailed answers, diagrams and explanations in the solutions to help you understand the chapter thoroughly. You will be able to understand the importance of the human eye, the different parts of eyes and how they perform their functions. You will also study the defects in the eyes and how they are treated.

Xam Idea Class 10 Science Chapter 11 The Human Eye And The Colourful World exercises contain 6 sections. These sections include very short questions, short questions, long questions as well as HOTS or higher-Order Thinking Skills questions. In these 6 sections, you have to face a total of 50 questions that are going to check your knowledge about the chapter. You will learn how hypermetropia is caused, how myopia is treated, the process of dispersion of white light and the reason sky appears reddish at the time of sunsets.

We have provided the best and easy answers for all Xam Idea Class 10 Science Chapter 11 The Human Eye And The Colourful World exercise questions. Every question is solved in a stepwise fashion to ensure maximum clarity. We have followed NCERT syllabus for Class 10 Science while formulating the solutions. You will be able to understand the complete chapter in a short amount of time with the help of our Xam Idea Class 10 Science Solutions for Chapter 11 The Human Eye And The Colourful World.

Important Topics for Xam Idea Class 10 Science Solutions Chapter 11 The Human Eye And The Colourful World

Human Eye 

  •  A Sensitive sense organ
  • It acts like a camera, enabling us to capture the colourful picture of the surroundings.
  •  It shapes an altered, genuine picture on light-touchy surface Retina.

Various Parts of the Eye and their Functions

  1. Cornea: It is a meagre layer through which light enters. It frames the straightforward lump on the facade of the eyeball. The vast majority of the refraction happens at the external surface of the cornea. 
  2. Eyeball: It is approximately spherical, with a diameter of about 2.3cm.
  3. Iris: It is a dim strong stomach that controls the size of the student. It is behind the cornea.
  4. Pupil: It manages and controls the measure of light entering the eye. It is the dark opening between watery funniness and a focal point.
  5. Crystalline Eye Lens: Provide the focussed genuine and reversed picture of the item on the retina. It is made out of a sinewy, jam-like material. This is a raised focal point that combines light at the retina.
  6. Ciliary Muscles: It helps to change the curvature of the eye lens and hence changes its focal length so that we can see the object placed at different positions.
  7. Retina: Thin membrane with large no. of sensitive cells. When an image forms at the retina, light-sensitive cells get activated and generate electrical signals. These signs are sent to the cerebrum by means of the optic nerve.  The brain analyses these signals after which we perceive objects as they are.

Persistence of Vision: It is the time for which the sensation of an object continues to thin the eye. It is about 1/16 of a second.

Power of Accommodation: The ability of the eye lens to adjust its focal length is called accommodation with the help of ciliary muscles.

Ciliary Muscles

Relaxed :

  1. Eye lens become thin
  2. Increases the focal length
  3. Enable us to see the distant object clearly

Contract : 

  1. Eye lens becomes thick 
  2. Decreases the focal length 
  3. Enable us to see the nearby object clearly

Near Point of the Eye: It is 25cm for a normal eye. The base separation at which article can be seen most unmistakably without strain  

Far Point of the Eye: It is infinite for a normal eye. It is the farthest point up to which the eye can see the object.

Defects Of Vision and Their Correction 

  1. Cataract: The picture can not be seen unmistakably in light of the fact that eye focal points become smooth and shady. This condition is known as cataract, it can cause a complete or partial loss of vision.

 This can be revised by careful evacuation of additional development 

  1. Myopia : (Nearsightedness)

 An individual can see close by objects unmistakably, yet can’t see far off items particularly. 

The Reason for defect

  1. Excessive curvature of the eye lens (thick, decrease focal length)
  2. Elongation of the eyeball.

Correction of Myopia

Amended by utilizing a Concave Lens of fitting force.

  1. Hypermetropia: (Far- Sightedness) 

 An individual can’t see close by objects obviously yet can see far off items unmistakably. The picture shaped at a point behind the retina The Reason for deformity

The Reason for defect

  1. Increment in the central length of the eye focal point (Thin eye lens)
  2. The eyeball has gotten excessively little. 

Correction of Hypermetropia

Corrected by utilizing a Convex Lens of proper force

  1. Presbyopia:

As we become old, the intensity of settlement of the eye typically diminishes, the close to point step by step retreats away. This deformity is called Presbyopia. An individual may experience the ill effects of both nearsightedness and hypermetropia.

Reason of defect:

The gradual weakening of ciliary muscles and decreasing the flexibility of the eye lens.

Correction of Presbyopia:

 Using a Bifocal lens with appropriate power.

Bifocal lenses consist of both concave and convex lenses, the upper position consists of the concave lens, and the lower portion consists of a convex lens.

Refraction of Light Through a Prism


  •  It has two triangular bases and three rectangular sidelong surfaces. 
  •  These surfaces are slanted to one another. The point between its two parallel appearances is known as the Angle of Prism.

Splitting of White light into a band of colours

  • The band of the hued segments of the light pillar as considered Spectrum that is VIBGYOR
  • The parting of light into its segment hues is called Dispersion.  
  • The different component colours of light bend at different angles with respect to incident angle the red light bends the least while the violet bends most.

Issac Newton 

  • He was the first, who obtained a spectrum of sunlight by using a glass prism.
  • He tried to split the spectrum of white light more by using another similar prism, but he could not get any more colours.
  • He rehashed the investigation utilizing the second crystal in a rearranged position concerning the primary crystal. Permitted all the shades of the range to go during that time crystal.
  •  He presumed that the sun is comprised of seven noticeable hues ‘VIBGYOR’


It is the range of daylight in nature It is framed because of the scattering of daylight by the small water bead, present in the environment.

Atmospheric Refraction 

Advance Sunrise and Delayed Sunset 

This is also due to atmospheric refraction. Because this sun is visible about 2 minutes earlier than the actual sunrise and about 2 minutes after the actual sunsets. Apparent flattening of the sun’s disc at sunset and sunrise is due to atmospheric refraction.

Clouds Appear White: The size of the water droplet (scattering particle) is very large, hence scattered all wavelengths of light almost equally.

The Colour of the Sky is Blue: The molecules of air and other fine particles in the atmosphere have a size smaller than the wavelength of visible light. Since the blue has a shorter wavelength than red, hence it will scatter the most.

According to Rayleigh Scattering:

  • Scattering of light a 1/ 4 ( l – Wavelength) 
  • Scattering of light decreases with an increase in wavelength

Scattering Phenomenon if there is no atmosphere on earth: There will be no scattering and the sky will appear dark.

The danger signal or sign made of red colour

Red colour scattered the least when strikes the small particle of fog and smoke because it has the maximum wavelength (visible spectrum). Hence at a large distance also, we can see the red colour clearly.

Sun appears White at Noon 

At noon, the sun is overhead and sunlight would travel a shorter distance relatively through the atmosphere. Hence, at noon, the Sun appears while only little of the blue and violet colours are scattered.

Exercise Discussion of Xam Idea Class 10 Science Solutions Chapter 11 The Human Eye And The Colourful World

Very Short Answer Type Questions

There are a total of 11 questions and each question contains 1 mark. The meaning of colour blindness, what do you understand by a spectrum of white light are some examples of those that are given to you in this section.

Short Answer Type Questions- I

This contains only 8 questions each of 2 marks. This section helps you to cover up your reason section of the chapter. The reason why we see colours, why are danger signal lights red in colour are examples of the questions that are there in this section.

Short Answer Type Questions- II  

 In this section, you are going to face 14 questions each of 3 marks. These questions are very important as they cover up the most examinable topic like what is presbyopia, what is astigmatism, etc.

Long Answer Type Questions  

In this section, you have only 5 questions and each question contains 5 marks. Most of the questions in this section contain diagrams, so this section covers up your important diagrams. What is the dispersion of light? What is the cause of dispersion? Draw a diagram to show the dispersion of white light by a glass prism is an example of the questions that are there in this section.

Higher-Order Thinking Skills (HOTS) 

In this, you have to face 6 questions that are going to check your higher-order thinking skills. Why sometimes haloes or rings are observed around the moon or sun is an example of the questions that you are going to face in this section.

Value-Based Question

In this section, you answer 6 questions and these questions are going to check the values that you learn from the chapter.

Why Use Xam Idea Class 10 Science Solutions Chapter 11 The Human Eye And The Colourful World By Instasolv?

  • Our subject experts have provided easy to understand and 100% accurate Xam Idea Solutions Chapter 11 The Human Eye And The Colourful World. 
  • Our Xam Idea solutions for Class 10 Science are based on the latest CBSE syllabus.
  • They help you to cover up your syllabus in very less time so that you can save you time for revision.
  • Our easy explanations of the typical concepts of light and spectrum of light will help you prepare well for your board exams in Class 10.