Does wave speed vary through different mediums just as our speed does?
Imagine having to run a race through an Olympic-sized pool instead of around a track. You would notice that the water in the pool is able to resist your movement and slow you down. On the other hand, running around the track is much more possible because the air resistance acting on your limbs is almost negligible. How about running through a block of ice? You would probably be frozen beyond even the slightest movement.
So why is movement through air so easy yet virtually impossible through a solid? This has to do with the movement of particles in each state of matter. Gas particles are free to move everywhere and therefore end up spaced out from each other, allowing us to move through air effortlessly. While liquid particles are very close together, they are allowed to slide past each other, which gives us some degree of movement in water. Since solid particles are tightly packed and only able to vibrate in place, we cannot push past them.
Like humans, waves have varying degrees of movement through the different states of matter. However, sound waves move by using molecules and not pushing past them, while electromagnetic waves do not require molecules to travel. How do these facts make circumstances different?
1. Based on the descriptions of particle motion in different states of matter, rank the three states from least to most dense.
2. Does electromagnetic radiation move faster through gases or solids? Explain.
3. We have learned that sound waves interact with particles differently than physical objects like humans do. Based on this, rank the three states of matter from fastest to slowest sound wave motion.
4. Considering your answer to the previous question, do sound waves move faster through more dense or less dense mediums? Explain.
5. Research: What do electromagnetic waves move fastest through?