PADI Divemaster Certification Practice Exam

When is sound traveling more efficiently through a medium?

1. When the medium is less dense

2. When the medium is more elastic

3. When the medium is stable

4. When the medium contains water

The correct answer is: When the medium is more elastic

Sound travels more efficiently through a medium that is more elastic. Elasticity refers to the ability of a material to return to its original shape after being compressed or otherwise deformed. When a medium is more elastic, the particles within it are able to transmit sound waves more effectively. This is because elastic materials can transmit vibrations faster due to their ability to quickly return to their original position, thereby facilitating faster energy transfer between particles. In contrast, less elastic materials may not transmit sound waves as efficiently, since the energy can be lost in the deformation process. The density of the medium can also play a role, but it is elasticity that has a more direct impact on sound transmission efficiency. Thus, a highly elastic medium will enable faster propagation of sound compared to a medium that is less elastic, regardless of its density.