What are longitudinal waves

In this case, Individual particles of wave move in direction of propagation of waves

In easy language, particles of medium move back and forth (left and right) making nearby particles of medium vibrate


If we stretch a slinky, it moves left and right (in the direction we put force)


What are Transverse Waves

In this case, particles of medium oscillate up and down at right angles to the direction in which the wave is moving.


If we move a slinky up and down, the wave moves to the right side but slinky moves up and down (right angle to direction of wave


See this image

Transverse Waves GIF

In the top wave, particles move perpendicular to direction of wave. So, it is a transverse wave

In bottom wave, particles move parallel to direction of wave. So, it is a longitudinal wave

Another example can be

Transverse and Longitudanal Waves GIF


Are sound waves Longitudinal or Transverse ?

Sound waves are longitudinal waves

It is because sound waves move in back and forth direction


When an object vibrates, it forces the particles of medium around it to also vibrate (move to and fro)

They cause the neighbouring particles to vibrate and so on

This process continues until the vibrations reach the person's ear and we are able to hear sound


What is the difference between longitudinal and transverse waves?

Link to Extra Question



NCERT Question 4 - Why is sound wave called a longitudinal wave?

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.