How often do we encounter waves in our daily lives?
Have you ever seen a snake slithering across a forest floor? Did you notice the side-to-side motion it made? This creature actually uses its body as transverse waves to push against the ground or water and create movement. Like in any medium carrying a transverse wave, snakes displace the parts of their body perpendicular to whichever direction they are trying to go.
Since snakes may not be the safest to be around, a slinky can easily demonstrate transverse waves. Watch this video to see how.
Recall that longitudinal waves cause the medium to vibrate parallel to the direction of the waves motion. One of the most common examples of this type of wave is sound. When speakers vibrate, they cause air particles around them to vibrate in the same pattern. These particles oscillate back and forth, being compressed and uncompressed (opposite of compression is rarefaction). When these vibrating particles reach us, they cause our eardrums to vibrate in the same pattern as well - which we perceive as sound.
A slinky is also a good way to show longitudinal waves, since we cannot see sound. Watch the following video.
As an experienced surfer maneuvers his board on the ocean, he searches for the biggest waves to test his skill and enjoy the thrill. Ocean waves like the ones surfers use to move are a combination of different wave types. In general, water waves can be classified as surface waves. These are a combination of longitudinal and transverse waves.
1. Are there any other creatures that might use transverse waves? Longitudinal waves?
2. Describe how longitudinal waves work in a slinky. (How do the coils interact with each other?)
3. How would you expect ocean waves to move, given that surface waves combine two types of waves? (Hint: What happens when you add left-to-right and up-to-down motion simultaneously?)
4. Surface waves can also apply to earthquakes. Research: What are they generally called when describing earthquakes? Which type causes the most damage during an earthquake and why?