Where do sand waves travel faster? Through less dense material because the molecules in a loosely packed medium collide less frequently. To less dense material because the molecules in a loosely packed medium collide more frequently. Dents or material molecules in a medium collide more frequently. The molecules packed medium collide less frequently.

Sand waves travel faster through less dense material because the molecules in a loosely packed medium collide less frequently. This allows the waves to propagate more easily and quickly through the material. When the material is more densely packed, the molecules collide more frequently, causing the waves to move more slowly.