Chapter 9 Notes | Physics 1st Year
“Work and Energy”
- Huygen’s Principle
- Interference of Light Waves
- Young’s Double Slit Experiment
- Interference in thin films
- Newton’s Rings
- Michelson Interferometer
- Diffraction of Light
- Diffraction due to Narrow Slit
- Diffraction Grating
- Diffraction of X-Rays by crystals
- Difference b/w Interference and Diffraction
- A surface passing through all the points undergoing a similar disturbance (i.e. having the same phase.) at a given instant is called wave-front
- When the disturbance is propagated out in all directions from a point source , the waveform in this case are spherical.
- Radial lines leaving the point source in all directions represent rays.
- The distance between two consecutive waveform is called wavelength.
- Huygens principle states that all points on a primary wave-front can be consider as the source of secondary wavelets.
- When two or more waves overlap each other, there is resultant waves, This phenomenon is called interference.
- Constructive interference occurs when two waves, travelling in the same direction overlap and the amplitude of the resultant wave is greater than either of the individual waves.
- In case of destructive interference , the amplitude of the resulting waves is less than either of the individual waves.
- Newton’s rings are circular fingers formed due to interference in a thin air film enclosed between a convex lens and a flash glass plate.
- Michelson’s interference is used for very precise length measurements. the distance l of the moving mirror when m fringe move in view is mλ/2.
- Polarization of light proves that light consists of transverse electromagnetic waves