PowerPoint Presentation (A partial fulfillment in Physics) Presented By: Mary Joice Avinante Orlane Marybhell Dimaunahan Klarabelle Villafranca Nikko Samonte Jonas Villaveza IV-1 BaStateU ARASOF Nasugbu Batangas A.Y.2011-2012
What is Light? This question has been a puzzle for centuries. People once thought light was something that traveled from a person’s eyes to an object and then back again. If anything blocked the rays from the eyes, the object could not be seen. Since the 1600’s, scientists have made many discoveries about light.
Light-An electromagnetic wave, a form of energy that cantravel freely across space.- an electromagnetic radiation in the wavelengthrange extending from about 0.4 micro to about 0.7micro or perhaps more properly, the visual response toelectromagnetic radiation in this range.-a transverse wave, meaning that the vibrations areperpendicular to the motion and speed of the wave.
Different Theories About LightCorpuscular theory -light consist of tiny particles that travel in straight lines through space. Sir Isaac Newton called these particles corpuscles.
Wave theory -Christian Huygens asserts that light is a form of wave motion sent out by luminous bodies.
Electromagnetic theory -James Clark Maxwell explains that light is the result of the oscillations of the electrically charged particles of the atom.
Quantum theory -Max Planck advanced the idea that light is an energy called photons or quanta which are transmitted in small bundles or quantities from luminous bodies and which, upon entering the eyes, make us able to see.
Characterization of light Polarized light- a form of light that vibrates in one plane only.
Coherent light-is a form of light, the constituentwave trains of which are emitted by single source andmove in unison. This form of light comes from laser.
Interference - phenomenon of light or any other types of waves in which two or more waves can combine to yield a resultant wave whose amplitude or intensity maybe greater or less than the component wave.
Types of Interference Constructive Interference -the two crest add together to give a larger crest. It gives a brighter light than either wave would have separately. Destructive Interference -the trough reduces the height of the crest, leaving the spot dim or even dark.
Sources of LightNatural sources of lightSunStars
Artificial Sources of LightElectric light bulbsNeon Signs
Different Laws Law of Reflection -when light strikes an object, it may be reflected, absorbed or refracted depending upon the nature of the surface of the material.
Law of Refraction -when a light ray passes obliquely from one medium to a more dense optical medium, it is bent toward the normal.
How is light wave transmitted? Transparent body -one which transmits light readily Translucent body -one which transmits some light, but much of the light scattered or diffused. Opaque body -one which does not allow or transmit light at all.