10. Light-Reflection and Refraction-Refraction of light Science Class 10 In English-CBSE Notes
Explore science cbse notes for Class 10 Chapter 10. Light-Reflection and Refraction Topic Refraction of light in English medium for exams preparation.
10. Light-Reflection and Refraction-Refraction of light Science Class 10 In English-CBSE Notes
Popular Topics Covered
Our study material includes
- cbse notes for class 10 science chapter 10. Light-Reflection and Refraction topic Refraction of light in english
- class 10 science chapter 10. Light-Reflection and Refraction cbse notes
- cbse class 10 science chapter 10. Light-Reflection and Refraction notes in english
- class 10 science chapter 10. Light-Reflection and Refraction study notes
- class 10 science chapter 10. Light-Reflection and Refraction revision notes
- cbse notes for class 10 science chapter 10. Light-Reflection and Refraction
- class 10 science chapter 10. Light-Reflection and Refraction summary notes
- cbse class 10 science chapter 10. Light-Reflection and Refraction quick notes
All Topics Chapter 10. Light-Reflection and Refraction
- 1. Introduction
- 2. Refraction of light
- 3. Refraction by Spherical Lenses
- 4. Image Formation by Lenses
- 5. page 5
Notes
10. Light-Reflection and Refraction-Refraction of light Science Class 10 In English-CBSE Notes
10. Light-Reflection and Refraction
Refraction of light
Chapter 10. Light-Reflection and Refraction
Refraction of light:
When a ray of light enters from one transparent medium to another transparent medium it changes its direction or it bends. This bending of light path is called refraction of light.
The refraction of light only takes place through transparent materials like glass, air and water etc.

There are two situation of this bending.
(i) When a ray of light enters from rarer medium to denser medium it bends towards the normal.
(ii) When a ray of light enters from denser medium to rarer medium it bends away from normal.
Cause of the refraction of light: The refraction of light occurs due to changing in speed of light it enter on transparent medium to another.
The Law of refraction:
The following are the laws of refraction of light:
(i) The incident ray, the refracted ray and the normal to the interface of two transparent media at the point of incidence, all lie in the same plane.
(ii) The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of a given colour and for the given pair of media. This law is also known as Snell’s law of refraction.
Snell's Law: The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of a given colour and for the given pair of media. This law is also known as Snell’s law of refraction.
Denser Medium: The medium which has greater refractive index is called dender medium. The particles of this medium is denser.
Rarer Medium: The medium which has smaller refractive index is called rarer medium.
Refractive Index: The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of a given colour and for the given pair of media. This constant value is called refractive index of the second medium with respect to the first medium.

- The refractive index can be linked to an important physical quantity, the relative speed of propagation of light in different media. It turns out that light propagates with different speeds in different media. Light travels the fastest in vacuum with the highest speed of 3×108 m s–1.
- In air, the speed of light is only marginally less, compared to that in vacuum.
- It reduces considerably in glass or water. The value of the refractive index for a given pair of media depends upon the speed of light in the two media.
- Refractive index with higher value of material has less speed of light through it.
- Refractive index with lower value of material has high speed of light through it.
Example: The refractive index of diamond is 2.42, it means the ratio of speed of light in air and speed of light in diamond is 2.42. Diamond has higher refractive index and when the light will pass through it, the speed of light will be less. The material media of higher refractive index reduce the speed of light than normal and the material media of lower refractive index increase the speed of light when pass through it.
Absolute refractive index of some material media:

An optically denser medium may not possess greater mass density. For example, kerosene having higher refractive index, is optically denser than water, although its mass density is less than water.
Optically Denser Medium: In comparing two media, the one with the larger refractive index is optically denser medium than the other.
Optically Rarer Medium: In comparing two media, the one with the lower refractive index is optically rarer medium than the other.
Refractive Index of Medium2 with respect to Medium1:
The refractive index of medium 2 with respect to medium 1 is given by the ratio of the speed of light in medium 1 and the speed of light in medium 2. This is usually represented by the symbol n21.

Example: The speed of light in air is 3 x 108 ms-1 and the speed of light in water is 2.25 x 108 ms-1. Find the refractive index of water with respect to air.
Solution: Speed of light in air = 3 x 108 ms-1.
Speed of light in water - 2.25 x 108 ms-1.


Refractive Index of Water is 1.33
Refractive Index of Medium1 with respect to Medium2:
The refractive index of medium1 with respect to medium 2 is represented as n12. It is given by

Example: Speed of light in water is 2.25 x 108 ms-1 and the speed of light in Kerosene is 2.08×10⁸ ms-1. Find the Refractive index of water with respect to Kerosene.
Solution: Speed of light in water (V1) = 2.25 x 108 ms-1.
Speed of light in Kerosene (V2) = 2.08 x 108 ms-1.

Refractive Index of water = Speed of light in Kerosene (V2)/Speed of light in water (V1)
= 2.08 x 108 ms-1/2.25 x 108 ms-1
= 2.08/2.25
= 0.924
Refractive Index of water with respect to Kerosene = 0.924
Questions for Practice:
Q1. What is refractive index?
Q2. Write the law of refraction of light.
Q3. What are the two situation of bending the path of light during refraction of light.
Q4. The refractive index of diamond is 2.42. What is the meaning of this statement?
Q5. Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s–1.
Q6. Define Optically denser medium and Optically rarer medium.
Q7. Write the Snell's law.
Q8. The Refractive Index Of Kerosene Is 1.44 . Find The Speed Of Light In Kerosene.
Q9. You are given kerosene, turpentine and water. In which of these does the light travel fastest?
Q10. Give the examples of the medium having highest optical density.
Also give the example of the medium with lowest optical density.
All Topics Chapter 10. Light-Reflection and Refraction
10. Light-Reflection and Refraction-Refraction of light Science Class 10 In English-CBSE Notes
Hindi Medium Students/Teachers/Tutors:
All Chapters science Class 10
CBSE Notes for Class 10 science Chapter 10. Light-Reflection and Refraction – Refraction of light
The CBSE Notes for Class 10 science Chapter 10. Light-Reflection and Refraction – Refraction of light are prepared to help students understand every concept in a simple, clear, and well-organized manner. These notes are based on the latest CBSE syllabus and are suitable for regular classroom learning, homework, revision, and examination preparation. Every topic is explained using easy language so that students can learn important concepts without difficulty and develop a strong academic foundation.
Studying directly from the textbook is essential, but during revision students often need concise study material that highlights only the most important information. These chapter-wise notes provide exactly that. Instead of reading lengthy chapters repeatedly, students can quickly revise definitions, concepts, facts, examples, and important points in a short period of time. This approach saves valuable study time while improving understanding and retention.
Why Study Chapter 10. Light-Reflection and Refraction – Refraction of light Using Our Notes?
Every chapter contains several important concepts that require careful understanding. Our notes present these concepts in a logical sequence so students can connect ideas easily. Difficult topics are simplified with easy explanations, making learning enjoyable for students of different learning abilities. Whether you are preparing for classroom discussions, assignments, periodic tests, or annual examinations, these notes provide a reliable source for effective revision.
- Prepared according to the latest CBSE curriculum.
- Simple and student-friendly explanations.
- Chapter-wise organized content for easy learning.
- Important concepts, definitions, and key points included.
- Useful for quick revision before examinations.
- Supports self-study and classroom learning.
- Helps improve conceptual understanding and confidence.
- Suitable for homework, assignments, and test preparation.
Benefits of Reading CBSE Notes Regularly
Consistent revision is one of the most effective ways to achieve academic success. Reading CBSE Notes for Class 10 science Chapter 10. Light-Reflection and Refraction – Refraction of light regularly helps students remember important information for a longer period. Since the content is arranged systematically, students can identify important topics quickly and revise them whenever required.
These notes also help students improve answer-writing skills by presenting information in a structured format. Instead of memorizing lengthy paragraphs, students learn how to organize answers using important points and concepts. This not only improves writing quality but also increases confidence during examinations.
How to Use These Notes Effectively
To get the best results, students should first read the NCERT textbook carefully and understand the chapter. After completing the textbook, they should study these notes to reinforce important concepts. During revision, students can focus on highlighted definitions, important facts, and key ideas before solving textbook exercises and practice questions. This learning strategy improves both understanding and long-term memory.
Teachers and parents can also use these notes as a quick reference while helping students revise lessons or complete assignments. Since the content is concise and well-organized, it becomes easier to explain difficult topics within a limited amount of time.
Features of Our CBSE Notes
Every chapter on our platform is created with the objective of making learning easier for students. Our educational team regularly reviews and updates the content according to the latest CBSE guidelines so that students always receive reliable and accurate study material.
- Easy-to-understand chapter explanations.
- Important definitions and key concepts.
- Well-structured content for faster revision.
- Based on the latest CBSE syllabus.
- Helpful for school exams and annual examinations.
- Free online access on desktop and mobile devices.
Prepare Better with Chapter-wise CBSE Notes
Success in examinations depends on consistent practice and smart revision. These CBSE Notes for Class 10 science Chapter 10. Light-Reflection and Refraction – Refraction of light are designed to reduce study pressure by presenting important information in a concise and meaningful way. Students can use them throughout the academic session for daily learning as well as last-minute revision before examinations.
Along with these notes, students are encouraged to solve NCERT textbook questions, practice important questions, and attempt sample papers regularly. Combining concept-based learning with regular practice helps improve problem-solving ability, analytical thinking, and overall academic performance. With disciplined study habits and quality learning resources, students can build confidence, strengthen their understanding of every chapter, and achieve excellent results in school examinations.
10. Light-Reflection and Refraction-Refraction of light Science Class 10 In English-CBSE Notes Study Materials For Class 6 to 12
If you want to improve your academic performance, start studying with free CBSE notes for all classes. These notes are designed to make learning simple, clear, and effective for every student. Choose your class, explore the chapters, and begin your preparation with the latest cbse notes today.