When a ray of light passes from rarer to denser medium what happens to is wavelength?

Question

Does it increase or Decrease? Please Answer.

Answer 1

It's the FREQUENCY of light that's unaffected, meaning that the energy remains constant. However, the WAVELENGTH gets shorter, or "denser".

Let f = frequency, λ = wavelength, v = speed. Then,

f = v / λ

So, for constant f, if speed goes down, wavelength goes down too. That's what happens when light "passes from rarer to denser medium"

Energy of light is found as follows E = h f, which is a constant.

For those who gave other answers, here's a link to go read some really basic physics of light and refraction. Index of refraction n = w1 / w2, where w1 is wavelength in a vacuum, and w2 is wavelength in media Note that for most ordinary mediums, n is GREATER than 1.

Answer 2

when we consider a linear media
there is absolutely no wavelength change when light travels from
either rarer to denser or otherwise
however there is a change of angle
given by Snell's law
and also depending uopn the refractive index of the medium light
travels slower or faster i.e slower in a denser medium

Answer 3

when a ray of light passes from rarer to denser medium, its wavelength is increased.

Answer 4

The wavelength of light is unaffected by the medium of propagation.

However, the angle of propagation changes as the wave moves from one medium to another according to Snell's Law:

N1 sin(theta 1) = N2 sin(theta 2)

Where the N's are the refractive indices of the media and the thetas are the angle the propagating waves make with the normal vector of the surface.

Different wavelengths refract at different angles during media changes and get separated out, but the actual wavelengths remain the same.

Answer 5

The ray bends toward the normal because the speed of light is slower in the denser medium than it is in the less dense medium, and waves bend away from the direction where they travel faster and toward the direction where they move slower. Not part of the answer: But to understand this, imagine the light ray to have small "straight sticks" of wavefronts that are perpendicular to the light ray itself and lie in the geometric plane that contains both the light ray and the normal to the surface between the two media. One end of each little stick will reach the denser medium before the other end and be slowed down before the other end is slowed down. With that end slowing down first compared to the other end, the path of the stick will be bent toward the normal and the light ray's path with it. If you don't understand this second part, just ignore it and try to remember the first part above.

Answer 6

Wavelength does not ever change when light goes through different mediums. Its only the speed that changes. For eg. Light would travel around 1.3 times slower in glass than in vacuum..

Answer 7

wavelength of a lite ray travelling frm rarer to denser medium decr...
it can be easily seen frm the relation that wavelength of literay in a medium is inversely proportional to refractive index of the medium...wen lite travels frm rarer to denser medium,refractive index increaes...which implies that wavelength decreases....
n remember that it is the frequency of lite that does not vary with medium....

Answer 8

the wavelength remains unaffected when light travels from one transparent medium to another just the angle of the light changes.

Answer 9

the wavelength increases