Ans. LONGITUDINAL WAVES
In longitudinal waves, the particles of the medium move back and forth along the direction of propagation of the wave.
PRODUCTION OF LONGITUDINAL WAVES
Longitudinal waves can be produced on a spring (slinky) placed on a smooth floor or a long bench. Fix one end of the slinky with a rigid support and hold another end into your hand. Now give it a regular push and pull quickly in the direction of its length as shown in the figure.
A series of disturbances will start moving along the length of the slinky, Such a wave consists of regions called compressions and rarefactions. The compressions and rarefactions move back and forth along the direction of motion of the waves.
*
Examples: Waves produced in springs are longitudinal waves.