Sound waves are longitudinal waves, Sound waves are transverse wave, Difference between the transverse waves and longitudinal waves

 

Sound waves are longitudinal waves

 

Longitudinal waves are waves in which the vibration of the medium is parallel or along to the direction the waves travels and displacement of the medium is the same or the opposite direction of the wave propagation.

In the sound waves, the particles of the medium vibrate in the direction parallel to the direction of propagation of disturbances. Hence, the sound waves are also called as longitudinal waves.

Take an example:-

Take a slinky and hold the slinky from both sides and stretch the slinky. When we compress one end of the slinky and release it, it experiences a wave of the compression which travels to the length of it, stretching follows it. The coil of the slinky has a point that moves with the waves and returns from the same path. While returning, it passes from the neutral position and then again reverse its position. If we mark a dot on the slinky, we will find that the dot on the slinky will move back and forth parallel to the direction of the propagation of the disturbance.

 

The regions where the coils become closer are called compressions. And it is denoted by the letter C.

The regions where the coils are apart are called rarefactions. And it is denoted by the letter R.

Sound waves propagate in the medium as a series of the compressions and rarefactions. Now we can compare the disturbance of the slinky with the sound propagation in the medium. These waves are called longitudinal waves.

In these waves, the individual particles of the medium move in the direction parallel to the direction of the propagation of the disturbance.

The particles do not move from one place to another place but they oscillate back and forth from their position of the rest.

This is the exactly how the sound wave propagates. Hence sound wave are longitudinal waves.

 

Sound waves are transverse wave

 

Transverse wave is a wave whose oscillations are perpendicular to the direction of the wave. In the transverse wave, particles do not oscillate up and down about their mean position as the wave travels. Thus, the transverse wave is the one in which the individual particles of the medium move about their mean positions in a direction perpendicular to the direction of the wave propagation.

 For example:- when we drop a pebble in a pond, the waves on the water surface is an example of the transverse wave

 

light is a transverse wave.

Light is a transverse wave where the oscillations are the electric and magnetic fields. And these magnetic and electric fields are pointed at right angles to the ideal light rays that describe the direction of the propagation.

 

 

Light is not a mechanical wave

 

Light is not a mechanical wave because for light, the oscillations are not of the medium particles or their pressure or density. Hence light is not a mechanical wave.

 

 

Difference between the transverse waves and longitudinal waves

 

The major difference between the transverse waves and longitudinal wave are as follows:--

(1)                    Transverse wave is a wave whose oscillations are perpendicular to the direction of the wave.

  Longitudinal waves are waves in which the vibration of the medium is parallel or along to the direction the waves travels and displacement of the medium is the same or the opposite direction of the wave propagation.

 

(2)                   Transverse waves acts in two dimensions.

Longitudinal wave acts in one dimensions.

 

(3)                    In the transverse waves, The medium is moving perpendicular to the direction of the wave.

In the longitudinal waves, The medium moves in the same direction of the wave.

 

(4)                   Transverse waves  is made up of troughs and crests.

     Longitudinal wave is made up of rarefactions and compressions.

(5)                    Transverse waves can be propagate only through solids and at the surface of the liquid medium.

Longitudinal waves can propagate through any medium (like gas medium, solid medium water medium, extra).

(6)                    The graphically representation of the transverse waves are displacement-distance graph.

The graphically representation of the transverse waves are density-distance graph.

(7)                    Example of the transverse waves are water waves, electromagnetic waves.

Examples of the longitudinal waves are sound waves tsunami waves, vibration in the springs or slinky.

(8)                   Transverse waves can be polarized or aligned.

Longitudinal waves cannot be polarized or aligned.