Huygens Principle of Secondary Wavelets скачать в хорошем качестве

Huygens Principle of Secondary Wavelets

For more information: http://www.7activestudio.com info@7activestudio.com http://www.7activemedical.com/ info@7activemedical.com http://www.sciencetuts.com/ 7activestudio@gmail.com Contact: +91- 9700061777, 040-64501777 / 65864777 7 Active Technology Solutions Pvt.Ltd. is an educational 3D digital content provider for K-12. We also customise the content as per your requirement for companies platform providers colleges etc . 7 Active driving force "The Joy of Happy Learning" -- is what makes difference from other digital content providers. We consider Student needs, Lecturer needs and College needs in designing the 3D & 2D Animated Video Lectures. We are carrying a huge 3D Digital Library ready to use. Huygens Principle of Secondary Wave lets: According to Huygens theory a point source S sends out waves in all directions. In time to, the waves of light would reach a distance Cx to equally in all directions in space. Where, 'c' is the velocity of light. All the points where the waves have reached in the same time are on the surface of a sphere with S as centre and radius equal to Ct0. The sphere is depicted by a circle in the plane of paper. Since all the points on the surface of this sphere have received the waves at the same time t therefore these are vibrating in the same phase. So, this surface is called q wave front. A line drawn perpendicular to the wave front is called a ray of light. So, all the radii of there spherical wave front represent rays as shown in figure.In order to explain how a wave front is propagated forwards through a homogeneous isotropic medium.Christian Huygens made the following two assumptions: 1.Each point on a wave front acts as a fresh source of disturbance called as secondary wavelets. These wavelets spread out in the medium with the velocity of light in that medium. 2.The new wave front at any later time is obtained by taking the forward envelope of the secondary wavelets at that time.Let S be a point source of light which sends out spherical disturbances in the homogeneous and isotropic medium around it. Let AB be a trace of a spherical wave front at any instant t0. Each point on this spherical wave front is a source of secondary wavelets. Starting from different points of wave front at any instant t0. Each point of this spherical wave front is a source of secondary wavelets. Starting from different points of the wave front, the secondary wavelets will travel a distance CΔt in time Δt. So, each secondary wavelet will be a sphere of radius CΔt. The forward envelop CD of all the secondary wavelets gives the position of the new wave front after time Δt. So, a spherical wave front advances as a spherical wave front. If the radius of the original spherical wave front is infinitely large, then it appears as a plane wave front as shown in figure.It can be shown from considerations of superposition of waves and the phenomenon of interference that the amplitude of particles on a backward wave front is zero. Another important point to be noted is that only the point where the envelop CD touches the secondary wavelet is effective. The effects of all other points of the secondary wavelets cancel each other