Lesson 10 of 21 • 2 upvotes • 10:16mins
Reflection of sound wave. The reflection of sound follows the law "angle of incidence equals angle of reflection", sometimes called the law of reflection.The reflected waves can interfere with incident waves, producing patterns of constructive and destructive interference. This can lead to resonances called standing waves in rooms. It also means that the sound intensity near a hard surface is enhanced because the reflected wave adds to the incident wave, giving a pressure amplitude that is twice as great in a thin "pressure zone" near the surface. When sound waves in air (pressure waves) encounter a hard surface, there is no phase change upon reflection. That is, when the high pressure part of a sound wave hits the wall, it will be reflected as a high pressure, not a reversed phase which would be a low pressure. A positive or "high" pressure is one that is above the ambient atmospheric pressure and a negative or "low" pressure is just one that is below atmospheric pressure. A wall is described as having a higher "acoustic impedance" than the air, and when a wave encounters a medium of higher acoustic impedance there is no phase change upon reflection. On the other hand, if a sound wave in a solid strikes an air boundary, the pressure wave which reflects back into the solid from the air boundary will experience a phase reversal - a high-pressure part reflecting as a low-pressure region. That is, reflections off a lower impedance medium will be reversed in phase.
21 lessons • 3h 20m
Sound Wave Course Overview (in Hindi)
5:08mins
Nature and Propagation of Sound Wave (in Hindi)
10:19mins
Wavefront, displacement Wave and Pressure Wave (in Hindi)
13:10mins
Speed of Sound Wave in Material Medium (in Hindi)
7:14mins
Speed of Sound Wave in Solid and Gases (in Hindi)
8:37mins
(Hindi)Effect of pressure, temperature and humidity on the speed of sound in air
8:28mins
(Hindi) Intensity of sound wave
8:59mins
(Hindi) Appearance of sound to human ear
7:10mins
(Hindi) Interference of sound wave
10:14mins
(Hindi) Reflection of sound wave
10:16mins
(Hindi)Vibrations of air columns in closed organ pipe
7:45mins
(Hindi) Vibrations of air column in open organ pipe
10:47mins
(Hindi) Determination of speed of sound in air,Resonance Column Method
9:14mins
(Hindi)Kundt's tube experiment speed of sound in gas and rod
11:58mins
BEATS
12:36mins
Diffraction of sound wave
10:31mins
Doppler effect in sound wave.
9:58mins
Change in wavelength, Sonic Boom and Mach Number
9:19mins
Musical scale, acoustic of building, Reverberation Time, Echo
12:06mins
Numerical exercise no 01, based on sound wave
10:05mins
Numerical exercise no 02
6:21mins