UrbanPro

Take Class 12 Tuition from the Best Tutors

  • Affordable fees
  • 1-1 or Group class
  • Flexible Timings
  • Verified Tutors

When light travels from air to water ,why there is change in wavelength but not frequency

Asked by Last Modified  

Follow 3
Answer

Please enter your answer

Training Centre

According to wave nature of light, frequency is the no. of cycles / sec. As water is optically denser than air, the no. of cycles / sec, entering into another medium, is not changing but the distance covered in one cycle is changed,
Comments

I can help students understand their subjects better from their position.

Fundameantally speaking, when you say you are passing light, you are basically passing photons from one medium to another. Hence, when light passes from one medium to another, the number of photons passing remain constant, just that the wavelength changes. as long as the number of photons are constant,...
read more
Fundameantally speaking, when you say you are passing light, you are basically passing photons from one medium to another. Hence, when light passes from one medium to another, the number of photons passing remain constant, just that the wavelength changes. as long as the number of photons are constant, the frequency cannot change. read less
Comments

IIT Educated and well experienced experts selecting only a few highly motivated and ambitious students

firstly the speed of light in any medium is v = 1/sq.rt(mu . epsilon) which is what james clerk maxwell proved. So if both mu and epsilon change when light enters water ... the speed of light should change. This takes care of the question as to why the speed should change. Now consider a light wave,...
read more
firstly the speed of light in any medium is v = 1/sq.rt(mu . epsilon) which is what james clerk maxwell proved. So if both mu and epsilon change when light enters water ... the speed of light should change. This takes care of the question as to why the speed should change. Now consider a light wave, with say 10 vibrations per second. There is no reason as to why the number of vibrations in air should change when light enters water. Say if light has to lose energy, it should lose amplitude. So the number of vibration must remain constant but since speed of light in medium = frequency . wavelength ...and since speed and frequency don't change therefore wavelength changes. Yet another way of looking at it is through experiment. "The color of light is not primarily dependent on the wavelength of the light, as most people probably think. A wavelength of 389 nm is violet light in a vacuum, where the index of refraction is 1.000. However, in a medium where the index of refraction is greater than 1.000, the wavelength of violet light is not necessarily exactly 389 nm. The color mainly is dependent upon the light's frequency, which is the number of waves of the light that pass a given point in one second. If the color of light was dependent on wavelength, its color would change when it entered a medium with a different index of refraction. But it doesn't. For instance, if you look at an object in air, and then jump into a swimming pool with the object and look at it under water, the color of the object will remain the same." source: http://www.tedmontgomery.com/remarks%5C08.1-12/optics/index.html Also there is a theoretical derivation as to why this happens which depends on solving maxwells equations at the boundary with boudary conditions such that the intensity of light in air equals the sum of intensities of light which is reflected and refracted at the interface. The result of solving with such boundary conditions is that we get a change on wavelength but not frequency. I hope this suffices Cheers read less
Comments

Tutor

Assuming color does not change, the wavelength and frequency cannot change thus velocity cannot change. Cute paradox! But there is a way out. We need to consider how light is transmitted through a material. What happens is the photons get absorbed by the atoms and re-emitted. Thus they start and stop...
read more
Assuming color does not change, the wavelength and frequency cannot change thus velocity cannot change. Cute paradox! But there is a way out. We need to consider how light is transmitted through a material. What happens is the photons get absorbed by the atoms and re-emitted. Thus they start and stop the velocity between atoms is still 3*10^8 m/s. It is sort of like cars in a city. They stop at every stop light then go to the speed limit between stop lights. The average speed for the distance is less than the speed limit read less
Comments

Now, let's take a glass-air interface and pass light through it. (In SI units) In one second, ? "crest"s will pass through the interface. Now, a crest cannot be distroyed except via interference, so that many crests must exit. Remember, a crest is a zone of maximum amplitude. Since amplitude is related...
read more
Now, let's take a glass-air interface and pass light through it. (In SI units) In one second, ? "crest"s will pass through the interface. Now, a crest cannot be distroyed except via interference, so that many crests must exit. Remember, a crest is a zone of maximum amplitude. Since amplitude is related to energy, when there is max amplitude going in, there is max amplitude going out, though the two maxima need not have the same value. Also, we can directly say that, to conserve energy (which is dependent solely on frequency), the frequency must remain constant. read less
Comments

B. Tech. ( Electronics and Communications ) with 72% aggregate

this is beacuse the energy remains same in both the media, and we know that E=hf, where E is the energy, h is the planck's constant and f is the frequency. therefore in case of refraction the bending of light solely depends on the wavelength and further to understand this, we know that wavelength= speed...
read more
this is beacuse the energy remains same in both the media, and we know that E=hf, where E is the energy, h is the planck's constant and f is the frequency. therefore in case of refraction the bending of light solely depends on the wavelength and further to understand this, we know that wavelength= speed of light/frequency of light and the speed of light changes from medium to medium, thus frequency remains constant,and only wavelength changes as it is directly proportional to the speed of light. hope thi sresolved ur problem :-) read less
Comments

Bachelor of Engineering (B.E.) in Electronics & Communication

The energy of the light is related to the frequency; when the light enters the medium there are interference patterns that cause the apperent speed of light to change; if the frequency changed, the energy would not be conserved. The wavelength changes to balance the change in speed
Comments

Msc

he energy of the light is related to the frequency; when the light enters the medium there are interference patterns that cause the apperent speed of light to change; if the frequency changed, the energy would not be conserved. The wavelength changes to balance the change in speed.
Comments

Vision For Young India

Light travels as waves, with the wavefronts perpendicular to the direction of motion.As light moves from air into water, it not only slows, but the wavelength changes.(Denser and rarer medium condition.). Interestingly enough, the frequency of the waves does not change as the light moves from air to...
read more
Light travels as waves, with the wavefronts perpendicular to the direction of motion.As light moves from air into water, it not only slows, but the wavelength changes.(Denser and rarer medium condition.). Interestingly enough, the frequency of the waves does not change as the light moves from air to water.As we know the wave's speed v is related to both the frequency f and the wavelength l : v = l/f. Combining the above expression for velocity with the definition of index of refraction, we find a relationship between the wavelength l = v/f in a medium and the wavelengthl 0 = c/f in vacuum: read less
Comments

Physics Professor

It will travel from rarer to denser.Structure of molecule in water stronger than air.
Comments

View 33 more Answers

Related Questions

What is an electric field?
Electric field is defined as the electric force per unit charge. The direction of the field is taken to be the direction of the force it would exert on a positive test charge. The electric field is radially...
Jyoti
0 0
7
What is meaning of sole trade concern ?
Sole trading concern is the simplest, oldest and the most natural form of business organization in private sector. In this form a single individual is solely responsible for providing the capital,...
Vidhya Vaibhava Education Institution

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

Introduction to physics
The nature around us is very colourful and diverse. Physics is the study of nature and its laws.Physics is an experimental science: Physicists observe the phenomena of nature and try to find patterns that...

Consignment Accounts By CA Prashanth Reddy
A. INTRODUCTION When goods are sent by one person to another to be sold by the latter on behalf and at the risk of the former, the transaction is known as consignment. The person who sends the goods...
F

Introduction To Accounting: Part 19: Verifiable Objective Concept
The Verifiable Objective Concept holds that accounting should be free from personal bias. Measurements that are based on verifiable evidences are regarded as objectives. It means all accounting...

Easy Way to Exam preparation
List out the chapters that you are studied and easy for you. List out the chapter that covers max marks and easy. List out sub topics names in each chapter and prepare each concept by understanding...

On GST road, There’s No Checking India
The ‘One Nation One Tax’ slogan isn’t just about uniform rate, it is also about removing check posts at borders, which often clog traffic for hours, delaying shipment of goods. While...
F

Recommended Articles

Radhe Shyam is a highly skilled accounts and finance trainer with 8 years of experience in teaching. Accounting is challenging for many students and that’s where Radhe Shyam’s expertise comes into play. He helps his students not only in understanding the subject but also advises them on how to overcome the fear of accounts...

Read full article >

Sandhya is a proactive educationalist. She conducts classes for CBSE, PUC, ICSE, I.B. and IGCSE. Having a 6-year experience in teaching, she connects with her students and provides tutoring as per their understanding. She mentors her students personally and strives them to achieve their goals with ease. Being an enthusiastic...

Read full article >

Swati is a renowned Hindi tutor with 7 years of experience in teaching. She conducts classes for various students ranging from class 6- class 12 and also BA students. Having pursued her education at Madras University where she did her Masters in Hindi, Swati knows her way around students. She believes that each student...

Read full article >

Mohammad Wazid is a certified professional tutor for class 11 students. He has 6 years of teaching experience which he couples with an energetic attitude and a vision of making any subject easy for the students. Over the years he has developed skills with a capability of understanding the requirements of the students. This...

Read full article >

Looking for Class 12 Tuition ?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you
X

Looking for Class 12 Tuition Classes?

The best tutors for Class 12 Tuition Classes are on UrbanPro

  • Select the best Tutor
  • Book & Attend a Free Demo
  • Pay and start Learning

Take Class 12 Tuition with the Best Tutors

The best Tutors for Class 12 Tuition Classes are on UrbanPro

This website uses cookies

We use cookies to improve user experience. Choose what cookies you allow us to use. You can read more about our Cookie Policy in our Privacy Policy

Accept All
Decline All

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 55 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 7.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more