Here's why:
* Longitudinal waves have particles that oscillate back and forth *along* the direction the wave is moving.
* Transverse waves, on the other hand, have particles that oscillate *perpendicular* to the direction of wave travel.
Think of a slinky! If you push and pull the slinky, the coils move back and forth along the direction of the slinky, making a longitudinal wave.
Examples of longitudinal waves include:
* Sound waves: Sound travels through air by compressing and expanding the air particles.
* Seismic P-waves: These are the primary waves that travel through the Earth's interior during an earthquake.
