when a light wave contact with mirror and reflection occur.what do you think about change of phase angle?

Question

my question is about change of phase angle of the wave,when one wave emitting from one source and contacts to mirror and reflect phase angle change or not change?

Answer 1

When a ray of light is reflected by a mirror a phase change of (pi )radian or 180 degree is introduced.

The ray must try to eneter a denser medium from a rarer medium. In otherwords, the reflection must take place in a rarer medium.

If the ray is reflected within a denser medium no phase change take place.( example in total internal reflection no phase change occurs.

To remember about phase change due to reflection, you can think of a car taking U turn. While taking U turn the car is turned 180 degree.

But reflection of light wave is not like the motion of a car.

Answer 2

Sure, the phase angle of a wave can change upon reflection. For example, a transverse wave sent through a rope tied to a wall will come back phase-inverted, that is, upside-down. This is why standing waves work in string instruments. The change in the phase angle of the reflection will depend upon the relative index of refraction between the two sides of the interface. You can work it out with Maxwell's equations using the appropriate boundary conditions (free charge=0, free current=0, tangential components of electric field continuous, normal components of magnetic field continuous).

The same sort of thing happens with waves on strings. If two strings are tied together and the wave is incident from the heavier to the lighter, then the reflected wave will be upright (no phase change) but if the incident wave is going from the lighter to the heavier, there will be an inversion.

Answer 3

I'm not understanding your question. Phase angle is the angle that describes the relationship between the observer and the source of illumination of the object being observed. I.e., when light reflects off of a mirror to your eye, the phase angle is established--it doesn't change. Change suggests that it was one thing before the light hit the mirror, and something else afterward, but there was no phase angle established until the light hit the mirror. Can you restate your question maybe?

P.S. I'd like to second J C's comment. The Internet is for everyone--not just self-righteous native English speaking jerks.

Answer 4

Are you sure you understand the meaning of the phrase "phase angle?" A change in phase angle would imply some sort of disturbance in the electromagnetic wave - I doubt that it would be caused by reflection.

If you mean the angle of reflection, I can answer your question with more certainty. The angle of reflection will be the same as the angle of incidence.

And flsred, not everyone who writes questions here is a native English speaker. If you can't deal with bad grammar and spelling, get off the Internet and go read a book instead. Like the Encyclopaedia Britannica.

Answer 5

The phase angle changes by either 0 or pi depending upon the angle of incidence, refractive index and polarization of the incident ray. For more infomation, study the Fresnel equations.

Answer 6

First, a simplistic vision, light allows a better view, better understanding. We oppose the Light to darkness. Then your thinking makes me think to "Allegory of the Cave" from Platon : People (who attached to their ignorance ) who refuse Light (of knowledge) even if people introduce them Light in order to a beneficial purpose for them! They refuse , they're strenghened by fear, prejudices, or just simple-minded. This light make them unable to see properly, it's the reason why no one want to see It. None wants to make the effort to see this dazzling Light precisely because it blinded even the blind! lol This Light is very Bright isnt-it?

Answer 7

While beating my chest....I thunk the English language was a farce.....could someone help me find my way out of the ridiculously tacit code phenomenon you hacks pass off as the most difficult yet articulate language on the planet....dumbass.

Answer 8

it opposes the angle that the light entered