Doppler’s Effect 

When the source of the sound and observer are at rest the frequency of the sound heard by observer which is emitted by source of the sound is not changed\. When the source of the sound and observer or both are in motion the frequency of the sound heard by observer which is emitted by […]


When two sound waves of same amplitude and nearly equal frequency move in the same direction then these two waves superimpose to each other giving rise to alternating hearing of the sound. This phenomenon is called Beat. The no of hearing produce in one second is beat frequency. Consider two waves having frequency f1 and […]

Intensity of sound 

Intensity of sound: The intensity of sound at a point is defined as the amount of sound energy crossing the point per unit area per second. Then the unit of intensity of the sound is given by j/m2s or wm-2.   Threshold of hearing: The threshold of hearing is the lowest intensity of the sound […]

Characteristics of musical sound 

1. Pitch: The pitch is the characteristics of a musical sound which depends upon the frequency. The sound with low frequency is low pitch able sound and the sound with high frequency is high pitch able sound.   2. Loudness: The loudness of musical sound is related to the intensity of the sound the higher […]

Vibration in the stretched string 

When a string of mass per unit length (m) under the action of tension; T; is set in to transverse vibration the velocity of the wave propagation through the string is given by m = t\m In such a vibration of the string the disturbance produced at one fixed end. Travels along the ¬†string and […]

Velocity of sound by resonance air column tube 

The experimental setup of resonance tube experiment to determine the velocity of sound in air is shown in figure, to find the velocity of sound in air the water level in the tube is brought close to the open end of the tube by changing the place of water reservoir. A tuning fork of frequency […]

End Correction 

In actual practice, antinode is not formed at the opened, but it is formed a little above from the open end. Then the difference between actual position of the antinode and the position f the open end is called end correction. According to the Rayleigh, “the end correction for the closed organ pipe is 0.3d […]

Open organ pipe 

The pipe in which the both of its ends are open is called open organ pipe. Flutes is the example of organ pipe. Different modes of vibration in open pipe: a. First mode of vibration:   In the mode of vibration in the organ pipe, two antinodes are formed at two open ends and one […]

Closed organ pipe 

The organ pipe in which one end is opened and another end is closed is called organ pipe. Bottle, whistle, etc. are examples of closed organ pipe.   The different mode of the vibration in the closed organ pipe is discussed as below.   i. First mode of vibration [N (a)] In the first mode […]

Organ Pipe 

Organ pipe is a pipe in which if the vibration is passed from the one end it is then reflected from the other end and stationary wave is formed in the pipe. There are two types of Organ pipe.