Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
16 Cards in this Set
- Front
- Back
|
Wave Front |
The locus of all particles which are vibrating the same phase |
|
|
Spherical Wavefront |
The waves from a point surface the wave friends are spherical and shape |
|
|
Cylindrical Wavefront |
When the source of light is linear in shape such as a rectangular slit the wave friend is cylindrical shape |
|
|
Plane Wavefront |
As a spherical or cylindrical weapon advances it's curvature decreases and becomes a plane way front |
|
|
Ray |
Anari drawn perpendicular to the wavefront in the direction of propagation of a wave |
|
|
Hugyens Principal |
According to hugyens theory each point on a wave front is a source of secondary waves which add up to give away friend at any later time |
|
|
Assumptions of Hugyens Wave theory |
1. Each point on the primary wavefront is acting as a fresh source for the secondary wavefront 2. The secondary wavelets spread out in all directions with the speed of light in the given medium. 3. The secondary wave friend is given by the forward envelope ie to find the new wavefront after time t draw spheres of radius vt from each point on the primary wave front |
|
|
Behaviour of Prism |
Consider a plane wave passing through a thin prism, since the speed of light waves is less in glass, the lower portion of the incoming wavefront will get delayed resulting in a tilt in a imaginary wavefront |
|
|
Behaviour of lens |
Consider a plane wave incident on a thin convex lens. the central part of the incident of wavefront traverses the thickest portion of the lens and is delayed the most. so the emergent wave front has a depression at the centre |
|
|
Behaviour of Mirror |
A plane wave is incident on a concave mirror and on reflection a spherical wave friend converging to the focal point |
|
|
Coherant Sources |
Two sources which emit light of same frequency are same wavelength with zero or constant phase difference |
|
|
Interference (Del) |
The phenomenon interference (mixing of light waves) is based on the superposition principle according to which a particular at a point in the medium, there resultant displacement produced by a number of waves is a vector some of the displacements of each waves |
|
|
Youngs Double Slit Experiment |
A British physicist Thomas young used a technique to explain the interference of waves from two coherent sources distance d apart. a screen is placed at a distance d from the two coherent sources. the spherical waves emerging from S1 and S2 will produce indifference fringes on the screen at the distance D |
|
|
Sustained interference |
The interference pattern in which positions of maxima and minimum of intensity do not changed with them is called sustained interference |
|
|
Conditions of sustained interference |
1. The two sources should continuously emit waves of same frequency 2. The two sources should be coherent |
|
|
Diffraction |
It is a phenomenon of bending of light around the corners of small obstacles and forming dark and right princess with decrease intensity |
