• Motivational
  • Board Exams
  • Exam Prep Tips
  • Science & Tech
Sunday, February 5, 2023
  • Login
Aakash BYJU'S Blog
  • Aakash Home
  • MEDICAL
  • ENGINEERING
  • FOUNDATIONS
  • TOPPERS SPEAK
  • Exam
    • NEET
      • NEET 2023 Eligibility Criteria
      • NEET 2023 Dates
      • NEET 2023 Exam Pattern
      • NEET 2023 Syllabus
      • NEET 2023 Application
      • NEET 2023 Admit Card
      • NEET UG 2023 Result
      • NEET 2023 Cut Off
      • NEET 2023 FAQ
    • JEE Main
      • JEE Main 2023 Eligibility Criteria
      • JEE Main 2023 Dates
      • JEE Main 2023 Exam Pattern
      • JEE Main 2023 Syllabus
      • JEE Main 2023 Application
      • JEE Main 2023 Admit Card
      • JEE Main 2023 Counselling
    • JEE Advanced
      • JEE Advanced 2023 Eligibility Criteria
      • JEE Advanced 2023 Dates
      • JEE Advanced 2023 Application
      • JEE Advanced 2023 Syllabus
      • JEE Advanced 2023 Maths Syllabus
      • JEE Advanced 2023 Physics Syllabus
      • JEE Advanced 2023 Chemistry Syllabus
  • NCERT Solutions
  • NEET PG
    • INI CET
No Result
View All Result
  • Aakash Home
  • MEDICAL
  • ENGINEERING
  • FOUNDATIONS
  • TOPPERS SPEAK
  • Exam
    • NEET
      • NEET 2023 Eligibility Criteria
      • NEET 2023 Dates
      • NEET 2023 Exam Pattern
      • NEET 2023 Syllabus
      • NEET 2023 Application
      • NEET 2023 Admit Card
      • NEET UG 2023 Result
      • NEET 2023 Cut Off
      • NEET 2023 FAQ
    • JEE Main
      • JEE Main 2023 Eligibility Criteria
      • JEE Main 2023 Dates
      • JEE Main 2023 Exam Pattern
      • JEE Main 2023 Syllabus
      • JEE Main 2023 Application
      • JEE Main 2023 Admit Card
      • JEE Main 2023 Counselling
    • JEE Advanced
      • JEE Advanced 2023 Eligibility Criteria
      • JEE Advanced 2023 Dates
      • JEE Advanced 2023 Application
      • JEE Advanced 2023 Syllabus
      • JEE Advanced 2023 Maths Syllabus
      • JEE Advanced 2023 Physics Syllabus
      • JEE Advanced 2023 Chemistry Syllabus
  • NCERT Solutions
  • NEET PG
    • INI CET
No Result
View All Result
Aakash Institute Logo
No Result
View All Result

Home » Board Exams » CBSE 10th Physics concept note: Importance of refraction in our daily life

    Talk to our expert



    Resend OTP

    By submitting up, I agree to receive all the Whatsapp communication on my registered number and Aakash terms and conditions and privacy policy

    CBSE 10th Physics concept note: Importance of refraction in our daily life

    Importance of refraction in our daily life while preparing for CBSE 10th Physics concept note:

    by Team @Aakash
    Mar 29, 2022, 4:09 PM IST
    in Board Exams
    0
    Refraction of light is the phenomenon of change in the path of light in going from one medium to another.

    What is the Importance of Refraction in Our Daily Life What is the Importance of Refraction in Our Daily Life

    0
    SHARES
    987
    VIEWS
    Share on FacebookShare on Twitter

    Ever wondered why a coin placed in a cup made of glass looks bigger than its actual size? This effect is caused by a phenomenon of light known as the refraction of light. Like the reflection of light occurs daily to provide us vision, refraction also occurs daily. From the twinkling of distant stars to the concept behind magnifying glass, everything is caused by the refraction of light. 

    Click here to read a detailed blog on the refraction of Light.

    “Refraction of the self-image reveals the shades encumbered inside a person, just like the refraction of light gives 7 shades.” 

    Table of Content
    1. Overview
    1. Refraction Versus Reflection
    1. Refraction Definition and Laws 
    1. Types of Refraction
    1. Effects of Refraction
    1. Refraction from a Prism
    1. Frequently Asked Questions

    Refraction Versus Reflection

    It is noticed that scholars get confused when asked the difference between reflection and refraction. Since they sound so much the same, it is possible to mix things up. Look at the table between reflection and reflection to grasp the difference between the two.

    Reflection  Refraction
    • The bouncing back of the light is known as the reflection of light. 
    • The bending of light when it passes from one medium to another is known as the refraction of light. 
    • The light is reflected in the direction of the source. 
    • The light is refracted in the opposite direction of the source.  
    • We see the real position of the image of objects through reflection. 
    • We see apparent positions of the image of any object through refraction. 
    • For example, your figure inside a mirror is caused by reflection. 
    • For example, the letters appear to be larger than their actual size when viewed from a magnifying glass. This effect is caused by the refraction of light. 

    Do at Home: Take a beaker (glass cup) and fill it with water. Place a pencil/pen inside the beaker and observe that the pencil seems broken when dipped in a beaker. This is the outcome of the refraction of light. 

    Many such instances related to refraction might be seen in our surroundings. Let us now learn the definition and Physics laws related to the refraction of light. 

    Refraction: Definition and Laws

    When light travels, it can pass from all transparent media. It is reflected from opaque or shiny surfaces. When the light goes from air to water, its speed changes. This is because different materials have different compositions. Now when a light ray passes from one medium to another it bends due to the change of speed in different mediums. This bending of light is termed refraction.  For understanding refraction, first, understand the following terms:

    Denser Medium: A medium is said to be denser if its refractive index is greater than the refractive index of the medium from where the light is coming. 

    Lighter Medium: A lighter medium has its refractive index less than the refractive index of the medium from where the light is traveling. 

    Refractive Index: It is defined as the ratio of the speed of light in a vacuum to the speed of light in any other medium like water, glass, etc. This is formulated as i = c/v. (where c = velocity of light in space and ‘v’ = velocity of light in other mediums) For example, the refractive index of air is approximately 1. This is the deciding factor for the speed of light in any medium.

    From the figure, you can see how the incident ray from air or space bends in a transparent substance. This is the depiction of the refraction of light.

    Refraction Laws

    Statement 1: The incident ray, refracted ray, and the normal from the point of incidence all are coplanar. This means that they all lie on the same plane. 

     

    Statement 2: The ratio of the incidence angle (see angle ‘i’ in the figure) and the angle of refraction (see angle ‘r’ in the figure) is always a constant term.  

     

    Sin iSin r= k

    The constant ‘k’ depends on the wavelength of the incidence ray and the 2 materials from which the ray is passing. 

     

    Curiously Enough: The second statement from the reflection laws is also known as Snell’s Law. 

     

    What Causes Refraction 

    When a light beam is an incident on the interface of two substances, its frequency remains constant. Light, on the other hand, travels at varying velocities in different materials. As a result, the wavelength (λ) of light at the interface varies. This, in turn, causes a shift in direction, or refraction.

     

    Types of Refraction

    There are primarily two types of refraction in nature, they are as follows:

     

    Refraction from lighter (rarer) to denser medium: This type of refraction occurs when the light travels from a substance having a less refractive index to a medium having a larger refractive index. In such cases, the light ray is bent towards the normal. 

     

    Refraction from denser to lighter (rarer) medium: In this type of refraction the light ray passes from a substance having a high refractive index to a medium having a less refractive index. In this refraction, the ray of light is bent away from the normal. 

     

    Effects of Refraction

    Refraction results in several effects like the enlargement of objects when viewed from lenses, the shifting of the real depth to an apparent depth, atmospheric refraction, and much more. Let us study them one by one:

     

    Normal Shift

    A normal shift occurs when an object is submerged in a liquid with a refractive index greater than the air. 

     

    • The object inside the liquid transmits light waves that reach our eyes. These light waves move straight until they interface between the liquid and air. 
    • On passing from the interface, they experience refraction and are bent away from the normal (because the light ray is going from a denser medium to a rarer medium).
    • The refracted rays reach our eyes. When the path of the light rays is traced back, all the light rays meet at a point that is above the actual object.
    • Thus we see the apparent position of the object instead of the real position. This is termed the normal shift.

    The same effect is seen in breaking a pencil when placed in a beaker. We see the apparent image of the pencil, which is above the actual pencil, giving the vision that the pencil is broken. 

    There are two cases of normal shift:

    Case 1: Observer in rarer medium, an object in a denser medium

    When the light rays travel from denser to rarer medium the image of the object appears above the actual object. This implies that the real depth is greater than the apparent depth of the object.

    Case 2: Observer in a denser medium, an object in rarer medium

    In this case, the image of the objects is seen below the actual object. The real depth is less than the apparent depth of the object. 

     

    Atmospheric Refraction

    Another very important effect of refraction is atmospheric refraction. This is caused by the bending of light from different layers of the atmosphere. Listed below are some important phenomena which occur due to atmospheric refraction. 

     

    1) Objects behind a fire seems in a flickering motion

    An object kept behind a fire, or hot surface seems to flicker when viewed through the air. Above the hot surface, the air gets lighter and rises. Cool air resides in the top space. The refractive index of cool air is greater than that of hot air. Because of the fluctuating refractive index of the medium, light rays seem to come from several directions. The apparent position fluctuates as a result.

     

    2) Stars and planets on the horizon looks higher than usual

    Because of atmospheric refraction, stars seem slightly higher than their true position when seen from closer to the horizon. The refractive index of the Earth’s atmosphere grows as we move from the sky to Earth. As a result, light from a star near the horizon bends towards the normal as it moves from a rarer to a denser medium resulting in the star seeming higher than the actual position.

     

    3) Twinkling of Stars

    The twinkling of stars is the result of two effects of nature. The first effect is the intensity that reaches from the star to our eyes. If the amount of light from the star is less, we see less brightness. On the other hand, if the amount of light is more, we see brightness in the star.

    The second effect is atmospheric refraction. The light from the stars bent multiple times before reaching our eyes. Due to changing atmospheric indices, we see the star’s apparent position, which creates the twinkling effect.

     

    Refraction From a Prism

    Refraction through a prism is a very important concept related to the refraction of light. A prism is a pyramidal-shaped glass that is encumbered by three refracting surfaces. The light on entering a prism is refracted toward the normal. It travels inside the prism until it escapes out through refraction again. This time the ray is refracted away from the normal. See the figure below:

     

    i is the angle of incidence 

    r1 is the refracting angle when light travels into the prism

    r2 is the refracting angle when the light escapes from the prism

    e is known as the emergent angle 

    δ is termed as the angle of deviation

    A is defined as the angle of the prism

    Also Read: Refraction and Dispersion of Light | Reflection of Light

     Important Notes:

    • When refraction happens in a prism, it is observed that A = r1 + r2 and i + e = δ + A.
    • The refractive index of surface AC = sin isin r1 and the refractive index of surface AB = sin r1sin e.
    • The scattering of light into its 7 constituent colours is a result of refraction from the prism. This was first recognised by Sir Issac Newton.

     

    The formation of rainbows is the practical application of refraction through prisms. The water droplets after a rain act like prisms and refract the sunlight to form rainbows. 

     

    Frequently Asked Questions (FAQs) 

    Q.1. What are the practical applications of refraction for humans?

    Ans: Refraction is used in multiple instruments, from telescopes to look for planets to microscopes for observing micro life. The projector in movie theatres enlarges the entire film according to the screen. Refraction is used in lenses and cameras. 

     

    Q.2. What makes the light bend during refraction?

    Ans: On passing from one medium to another, the speed of light changes. This change in the speed of light causes the bending of light during refraction. 

     

    Q.3. Why do we see the pool as less deep than its actual depth?

    Ans: The light from the surface reaches our eyes after bending, which gives us an apparent position of the surface instead of the real one. Therefore, a swimming pool appears to be less deep due to refraction properties. 

    Q.4. Which physical property doesn’t change during refraction?

    Ans:  The only physical parameter which never changes during refraction is the frequency of the light source. The frequency may vary from source to source. The frequency of the light ray before and after refraction remains unaltered. 

    Q.5. Is refraction important for competitive exams?

    Ans: Yes! The refraction of light is a critical concept concerning competitive exams. Questions about refraction through the prism and atmospheric refraction have appeared in the CBSE board and JEE Mains multiple times.  

    Also, visit the page to get a detailed understanding of the chapter refraction and reflection of light.

    Tags: CBSE Class 10CBSE ExamCBSE PhysicsCBSE Term 2
    Previous Post

    NEET 2022 Biology: What are the major differences between a plant & animal cell?

    Next Post

    Tips for parents to enhance their kid’s concentration ahead of CBSE Board Exams 2022

    Next Post
    What is Rotation and Revolution: Definition from CBSE Class 6 Geography

    Tips for parents to enhance their kid's concentration ahead of CBSE Board Exams 2022

    Leave a Reply Cancel reply

    Your email address will not be published. Required fields are marked *

    Contact form

      Talk to our expert



      Resend OTP

      By submitting up, I agree to receive all the Whatsapp communication on my registered number and Aakash terms and conditions and privacy policy

      Recommended

      Goa Board Result 2023 Released for Class 12th Term 1 Exams on result1.gbshse.in

      Goa Board Result 2023 Released for Class 12th Term 1 Exams on result1.gbshse.in, OMR Reverification Steps Here

      Feb 2, 2023, 5:11 PM IST
      TS SET Exam Date 2022 Announced on telanaganaset.org

      TS SET Exam Date 2022 Announced on telanaganaset.org, Check Complete Details Here

      Feb 2, 2023, 4:57 PM IST

      Trending

      JEE Main 2022 Marks vs Rank vs Percentile

      JEE Main Marks vs Percentile vs Ranks

      Feb 2, 2023, 2:09 PM IST
      What Is A Good Score/Rank In JEE Main?

      What is a Good Score in JEE Main 2023?

      Feb 2, 2023, 3:09 PM IST

      Popular

      ANTHE'19 DPT

      I registered for ANTHE 2019. How to access the Daily Practice Tests (DPT)?

      Jun 2, 2020, 12:11 PM IST
      This National Level Scholarship Exam offering upto 90% Scholarship for Students in VIII, IX & X Grades

      This National Level Scholarship Exam offering upto 90% Scholarship for Students in VIII, IX & X Grades

      Sep 2, 2022, 6:14 PM IST
      Aakash National Talent Hunt Exam 2018 – A Perfect Start

      Aakash National Talent Hunt Exam 2018 – A Perfect Start

      Jun 2, 2020, 1:10 PM IST
      COVID-19

      The Unsung Heroes of the COVID-19 Pandemic

      Feb 1, 2023, 5:53 PM IST

      Popular Web Stories

    • Documents Required for Medical Admission

    • Dilute vs Concentrated Solution

    • ANTHE Scholarship 2022

    • Destruction of Colloids

    • ANTHE Books

    • Top Medical Colleges in UP

    • Non Biodegradable Items

    • Sum of Circumference of Circles

    • Dithecous Anther

    • Isomers with Molecular Formula c5h12
    • Recent Posts

      • Goa Board Result 2023 Released for Class 12th Term 1 Exams on result1.gbshse.in, OMR Reverification Steps Here
      • TS SET Exam Date 2022 Announced on telanaganaset.org, Check Complete Details Here
      • NEET UG 2023 Highlights: NEET UG Notification Soon, Registration Likely to Begin this Week on neet.nta.nic.in
      • JEE Main 2023 Chemistry February 1 Shift 2 Question Papers and Solutions
      • JEE Main 2023 Maths February 1 Shift 2 Question Papers and Solutions

      Follow Us

      • NCERT Solutions for Class 6
      • NCERT Solutions for Class 7
      • NCERT Solutions for Class 8
      • NCERT Solutions for Class 9
      • NCERT Solutions for Class 10
      • NCERT Solutions for Class 11
      • NCERT Solutions for Class 12
      • NCERT Solutions
      • Other Text Book Solutions
      • Important Concepts
      • Ask And Answer
      • Aakash Answers

      Copyright © Aakash Institute

      No Result
      View All Result
      • Aakash Home
      • MEDICAL
      • ENGINEERING
      • FOUNDATIONS
      • TOPPERS SPEAK
      • Exam
        • NEET
          • NEET 2023 Eligibility Criteria
          • NEET 2023 Dates
          • NEET 2023 Exam Pattern
          • NEET 2023 Syllabus
          • NEET 2023 Application
          • NEET 2023 Admit Card
          • NEET UG 2023 Result
          • NEET 2023 Cut Off
          • NEET 2023 FAQ
        • JEE Main
          • JEE Main 2023 Eligibility Criteria
          • JEE Main 2023 Dates
          • JEE Main 2023 Exam Pattern
          • JEE Main 2023 Syllabus
          • JEE Main 2023 Application
          • JEE Main 2023 Admit Card
          • JEE Main 2023 Counselling
        • JEE Advanced
          • JEE Advanced 2023 Eligibility Criteria
          • JEE Advanced 2023 Dates
          • JEE Advanced 2023 Application
          • JEE Advanced 2023 Syllabus
          • JEE Advanced 2023 Maths Syllabus
          • JEE Advanced 2023 Physics Syllabus
          • JEE Advanced 2023 Chemistry Syllabus
      • NCERT Solutions
      • NEET PG
        • INI CET

      Copyright © Aakash Institute

      Welcome Back!

      Login to your account below

      Forgotten Password?

      Retrieve your password

      Please enter your username or email address to reset your password.

      Log In