There are four types of waves - mechanical, transverse, longitudinal, progressive.
- Mechanical Waves: which can exist in material media and follows Newton's laws.
- Transverse Waves: whose particles oscillate in a perpendicular motion of the direction of propagation of the wave.
- Longitudinal Waves: whose particles oscillate along the way of the propagation of the wave.
- Progressive Waves: When the waves move from one point of the medium to another is called progressive wave.
Wavelength of a wave: In the case of a progressive wave, the distance between two points in the same phase at that particular time period is known as the wavelength of a wave. The distance is twice the number of two consecutive nodes and antinodes.
Time Period of oscillation: Time taken to move through one complete oscillation.
Principle of superposition of waves: In a medium when multiple waves transverse simultaneously, the displacement is the algebraic sum of the displacements due to each wave. This phenomenon is referred to as the principle of superposition.
Standing waves: When two identical waves moving in opposite directions interfere, it results in a standing wave. These waves are characterized by the zero displacement locations which are fixed and are called as nodes and locations of maximum displacements called as antinodes.
Doppler Effect: The change in the frequency of a wave when the source or the observer or both are moving relative to the medium. This phenomenon is used in different scientific aspects such as planetary science wherein astronomers depend on this effect to identify planets exterior to the solar system. Doppler Effect is an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move towards (or away from) each other.