A stone is thrown on the still water of the pond. When the stone hits the water then the particles of water of that region start to vibrate. These vibrating particles vibrate the neighboring of particles. This the vibration reaches to the edge of the pond by vibrating the particles of water. The particles of water oscillate up and down but do not move forward. The periodic vibration that passes over the surface of water due to the oscillatory motion of the particles is called wave.

The mechanical energy produced due to the vibration of water particles is transferred from one place to another through vibration. So, energy is transferred from one place to another through wave.

The periodic motion of particles which transfers energy from one place to another through a material medium but does not displace the particles permanently is called wave. The wave produced in solid, liquid or gaseous medium is called mer anical wave. Water wave, sound wave etc. are mechanical waves. To transfer the mechanical wave elastic medium is needed. There is another type of wave that does not need any medium to propagate which are called electromagnetic wave.

 

The characteristics of waves are the followings:

  1. The wave is produced due to the harmonic motion of the particles but the particles are not displaced permanently.
  2. A medium is necessary for the propagation of mechanical wave.
  3. The wave transfers energy from one place to another.
  4. The velocity of wave depends on the nature of medium.
  5. The reflection, refraction and superposition occur in case of wave.