Question

what is sound wave called a longitude way​

Answer 1

For a sound wave traveling through air, the vibrations of the particles are best described as longitudinal. Longitudinal waves are waves in which the motion of the individual particles of the medium is in a direction that is parallel to the direction of energy transport.

Answer 2

Sound wave moves parallel to the medium in the direction of propagation . The particles of the medium does not move all the way it just move back and forth . It is the same way how a longitudinal wave propagate that is why sound waves are called longitudinal wave.