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# Relativity/Hello sir

Question
Sir

Sir what are laws of reflection, i.e. what is the exact meaning of them that they are pattern of reflection of light or what.?

Sir this may be appear like homwork question. But sir it is not an homework question, sir it is my confusion.or please sir please dont reply that itis out of my experyise. pLease answer to this question. Hope so it is clear.

Thankyou

Aishwaraymeti, please forgive me for misspelling your name in my last message.

I am not sure exactly what you mean by laws of reflection. So I will just discuss what happens to light travelling in a medium when it encounters a different medium.

The simplest wave I can think of is a wave in a rope. Suppose you tie a long rope around a tree and hold the other end of the rope in your hand some distance away.

Now when the tope is quietly hanging a bit loosely between you and the tree, suppose you quickly move your end up and then down. Then be still.

What happens to the rope is that a hump appears in the rope which travels down the rope to the tree. It does not stop, however. At the tree the hump disappears and a small valley starts travelling back to your hand,  This is reflection.

If your hand is very strong and does not move when the valley hits your hand, the valley disappears and another hump starts back to the tree. This another reflection. and so forth.

If you use a flashlight in a room walled with mirrors, you can get the same kind of behavior, namely a pulse of light going back and forth between two facing walls. This is reflection of light.

The light goes straight back to you if you aim the flashlight at itself. If you aim it a bit to the side, the light comes back to your side a bit. It is customary to measure the angle of the light beam before it hits the mirror to the perpendicular of the mirror. This is called the angle of incidence. The angle after reflection is called the angle of reflection.

The two angles, incidence and reflection, are equal. Perhaps this is one of the laws of refection you are talking about.

If all this is clear, does it answer any of your questions?

Uncle Ben

Relativity

Volunteer

#### Uncle Ben

##### Expertise

I can answer questions regarding Einstein's Theory of Relativity, particularly in Special Relativity. I will not answer homework questions or mathematical problems that require special symbols.

##### Experience

I have taught physics at the college level, undergraduate and graduate, for many years including Special Relativity. I have taught at Johns Hopkins, Case-Western, and MIT. I have also served as a staff member of the Commission on College Physics, which was supported by the National Science Foundation to recommend improvements in the curriculum of college physics departments in the US. I am also the author of a textbook titled Vector Calculus, which was used at MIT in the teaching of electromagnetic theory and relativity. My research interests were mainly in solid state physics, especially the properties of metals at low temperatures. I am listed in the publication known as American Men of Science.

Publications
I have dozens of papers published in the Physical Review and in the American Journal of Physics.

Education/Credentials
I hold a Ph.D. degree in physics from the Johns Hopkins University.

Past/Present Clients
Johns Hopkins University, Case-Western Reserve University, Massachusetts Institute of Technology, Empire State College, Georgetown University, Commission on College Physics, and UNESCO.