Question

The propagation of sound does not occur through a ..........

Answer 1

Hint: Sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid. What we hear is the effect produced because of the to-and-fro motion of the particles from any medium. The to-and-fro motion is referred to as vibration.

Complete answer:
 In simple words it can also be said that sound is a form of energy that causes a sensation of hearing in our ears. In terms of psychology, Sound can be defined as the reception of sound pressure waves and their perception by the brain.
There are five main characteristics of sound waves: wavelength, amplitude, frequency, time period, and velocity.
(A) Wavelength- The wavelength of a sound is the distance between adjacent identical parts of a wave.
(B) Frequency- The number of vibrations per second is called the frequency.
(C) Amplitude- The strength or level of sound pressure is called amplitude of the sound wave.
(D) Time period- The time period is the time taken by a complete cycle of the wave to pass a point.
(E) Velocity- The sound velocity through a given material is the distance that the sound energy will propagate in that material in a given time.
The propagation of sound does not occur through a vacuum. Sound cannot travel through vacuum due to the fact that there are no molecules that can be compressed and expanded in space.

Note:
The speed of light is much faster than the speed of sound in air. If we compare, the speed of sound in air is Surface Tension $343\dfrac{m}{s} $ and the speed of light is $ 3 \times {10^8}\dfrac{m}{s} $ . The speed of light is much faster than the speed of sound because light waves do not need a medium in which to travel but sound waves do.