A ray of light, a bunch of photons, hit a commom mirror, made of glass and a silvery paint behind. What happens then? Why the photons bounce back? Why the photons are not absorbed by the surface of the mirror? Why they bounce back in right angles?
Use mathematics if you want.
2006-11-17 09:10:47 · 4 answers · asked by silvafilho 1 in Science & Mathematics ➔ Physics
The experimental fact verified by experiments with light rays and mirror show that the happenings follow certain laws: If the light ray hits normally it comes back by the same path. If obliquely then it comes back obliquely equally inclined to the normal at the point of incidence and in the same plane of normal and the incident ray. But if you do experiment in which you also measure the intensity of light incident and reflected, then you find that the intensity of reflected light is slightly less. This shows that some light is either absorbed or scattered following no specific laws. Now this is the experimental fact. Now explanations. Explanation depends upon what you assume light to be made up of. If photons, then you know what happens to the table tennis ball when it hits the table without spinning. Same thing should happen to photons. That is how Newton explained the phenomenon considering light as consisting of particles. He called them corpuscles. But photon is not an ordinary particle in bulk. It is supposed to have dual nature. Its total energy is equal h multiplied by some frequency which is a wave characteristic. Ordinary particle can have all velocities ranging from zero to velocity of light. But photons move with only one velocity. So in case of bulky table tennis balls we say that they follow these rules of reflection which can be derived from mechanics but lose their little kinetic energy to the table and as sound. In case of photons this is not possible. So we say that if a bunch of photons are incident on a polished surface, there exists a maximum probability of following the laws of reflection, but the probability of the photon getting absorbed or getting scattered in any other direction is vey low but not zero. Similar expalnation can be thought of following the hypothesis that light is electromagnetic wave then we have to take the example of the mechanical waves and see how em wave is differen from them.
2006-11-17 12:03:14 · answer #1 · answered by Let'slearntothink 7 · 0⤊ 0⤋
The quality of the mirrors are indeed identical within all those known as human beings. Although: Some mirrors have developed wrinkles. Some mirrors have rips and tears. Some mirrors have developed small cracks. Some mirrors have minor blemishes. Some mirrors have become tarnished. Some mirrors have become fogged. Some mirrors have become clouded. Some mirrors are susceptible to this world's vast ocean of illusion. These human mirrors have a great deal more 'problematic qualities' than can possibly be spoken of. "One needs a Special Doctor that can spot all of these small imperfections within each individual mirror and suggest the best method for a proper cleansing." Special Doctors of this caliber are hard to find! If one cannot locate a Unique Special Doctor: One must purchase some windex and start cleaning ones own mirror. Some mirrors need abrasive cleaners, like a fine jewelers rouge. Some might even need an extra fine sandpaper. Some may just need to be cleaned off with a mild detergent, and then rinsed with some clear spring water. The conditions of the clarity of all mirrors vary. Everything has faceted layers. One must discover each of these faceted layers and commence cleaning. It is a near endless task that requires great patience. If a Unique Special Doctor happens to notice a human being experiencing difficulty in the mirror cleaning process, this Special Doctor may intervene and give one assistance in the necessary cleaning. May our mirrors shine with extreme radiance. May God's Peace and Patience be with us all.
2016-05-21 23:31:00 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Mirrors are generally made from silver on glass.
silver reflects light because electrons in the silver are free to oscillate when they are effected by the electric field of the photon. They create a perfect "mirror image" of the electric field which then heads off in the opposite direction.
To do the angle of incidence = angle of reflection takes a bit of careful work with Maxwell's Equations and the boundary conditions created at the silver surface.
Usually angle of incidence = angle of reflection is just assumed in early physics classes (with a few good hand waving explanations and some practical demonstrations).
2006-11-17 10:00:09 · answer #3 · answered by bubsir 4 · 1⤊ 0⤋
They bounce back because the surface of a mirror is smooth. If a wall or something was smooth with no dents or microscopically small holes, you could see yourself there too.
and they bounce at right angles because they travel at 90 degrees wherever they are coming from.
2006-11-17 09:15:27 · answer #4 · answered by LaMathrick B 2 · 0⤊ 1⤋