How does light propagate ? for class 6th NCERT
Answers
Explanation:
Sound is a sequence of waves of pressure which propagates through compressible media such as air or water. (Sound can propagate through solids as well, but there are additional modes of propagation). During their propagation, waves can be reflected, refracted, or attentuated by the medium. The purpose of this experiment is to examine what effect the characteristics of the medium have on sound.
All media have three properties which affect the behavior of sound propagation:
1. A relationship between density and pressure. This relationship, affected by temperature, determines the speed of sound within the medium.
2. The motion of the medium itself, e.g., wind. Independent of the motion of sound through the medium, if the medium is moving, the sound is further transported.
3. The viscosity of the medium. This determines the rate at which sound is attenuated. For many media, such as air or water, attenuation due to viscosity is negligible.