Sound propagates only through a material medium in wave form. How can you say that?

Sakshi Education

Medium: Light can travel through vaccum, where as sound requires a material medium for its propagation. A man standing on the surface of the Moon fires a pistol, another person standing besides him at a distance cannot hear that sound. Because there is no atmosphere on the surface of the Moon to propagate the sound energy. Wave Motion: If a person in a room talks to a man standing next to the wall of the room, the other person can hear him. This is because the sound can bend around the corners of the wall and travel to the next person. Only a wave can bend around the corners, this means sound travels in a wave form.

As the sound is propagating in a medium, in wave form and progresses in all directions from the source, the waves are called Progressives Waves. Progessive Waves are of two kinds-

1. Transverse Waves 2. Longitudinal Waves

Transverse Waves: In this type of waves, the particles in the medium will be vibrating perpendicular to the direction of motion of the wave. Ex: The waves formed in ropes when one end of the rope is tied to a support and the other end is moved up and down.
Longitudinal Waves: In this type of waves, the particles of the medium move about their mean position in the same direction (along) as that of the motion of the wave.

Ex:

The motion of the spring
propagation of sound wave in the gaseous medium (say Air)

A Transverse Wave is associated with 'crests' and 'troughs', and
A Longitudinal Wave is associated with 'Compressions' and 'Rarefactions'.
The particles vibrating in the medium will transfer only energy (sound) and they will not travel along with the wave.
In a wave, the distance between two consecutive particles which are in the same phase is called wavelength
The particles in both Transverse and Longitudinal Waves are making simple hormonic motion either of the waves can be represented by a sine wave.