Why ripple effect doesn't happen on air as it does on water?

In summary, a single disturbance can cause ripples on the surface of water because it is a surface effect. However, when air is disturbed, it creates pressure waves that move outward in all directions, which we perceive as sound. The difference lies in the medium and how we perceive the disturbances. While ripples can only exist on surfaces or boundaries between different mediums, sound waves can travel through different mediums and are not limited to surface effects. Both can produce single pulses, but sound waves have a wider range of energy levels and can propagate better than surface waves. Overall, the difference between the two is a matter of human perception and timescales.
  • #1
tsean88
3
0
Hi everyone,
I am wondering why a single disturbance can cause ripple on water surface but the same is not true when sound wave is made. When air is disturbed, only one pulse is made in one time. What set the difference?
Thanks in advance.
 
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  • #2
There are multiple pulses in air as well, but our ears don't pick up individual pulses. If the pulses are close together, we perceive them as a high-pitched sound; if they're a bit farther apart we hear them as a lower-pitched sound.
 
  • #3
Sound is transmitted by pressure waves - the air is slightly compressed by the "speaker", then relaxes - and the pressure waves move outward from the source, decreasing in intensity as they move outwards.

You may not see these "ripples" in the air, but you can hear them - and the ear is a complex device which can pick up quite faint sounds, though bats and owls have better hearing.

The ripples you see for water are a surface effect - but we are immersed in the air, so for us there is no surface ripple for sound. But you can indeed see it for very strong sound waves - both on a water surface, a drum head, or worst of all - in the after effects of an earthquake.
 
  • #4
Thanks for your reply, PED.
Now I think of that it's true when immersed in a body of water, one can only produce one pulse a time. I think ripples can only exist on surfaces or boundaries between different medium.
 
  • #5
tsean88 said:
Thanks for your reply, PED.
Now I think of that it's true when immersed in a body of water, one can only produce one pulse a time. I think ripples can only exist on surfaces or boundaries between different medium.

You can think whatever you want. That doesn't make it true. It's possible to produce a single ripple wave on either surface or bulk waves, but that's usually not what happens.
 
  • #6
  • #7
dauto said:
You can think whatever you want. That doesn't make it true. It's possible to produce a single ripple wave on either surface or bulk waves, but that's usually not what happens.

Hi dauto, thanks for replying.
Can you show me how to produce a single ripple water wave on the surface? Why do we usually have it like it is then? I'd appreciate it if you can tell me more details.

256bits said:
Here is a video describing ripples in a pond of water.
More interesting than you thought, I bet.
http://wn.com/capillary_wave

That's cool. Thanks man. Then how about other waves, do they act the same?
 
  • #8
What other waves do you refer to?
 
  • #9
tsean88 said:
Hi everyone,
I am wondering why a single disturbance can cause ripple on water surface but the same is not true when sound wave is made. When air is disturbed, only one pulse is made in one time. What set the difference?
Thanks in advance.
Bottom line is that exactly the same Maths describes all of these phenomena. A disturbance spreads out in all directions, whether it's a stone or a 'bang'.
Imo, the relative difference between the two things is a matter of Human Perception and the timescales involved. 'Ripples' spread out from any sound source and they bounce off walls and obstacles. That's all in three Dimensions, rather than the two Dimensions of a water surface. The waves are longitudinal, rather than surface waves but a single pulse in both cases behaves pretty much the same (once you scale the times appropriately).
Aamof, sound tends to propagate better than most surface waves, which is easily shown by clapping your hands together in a large cave or stone building - you can identify the reverberation for many seconds in some cases. Our hearing can detect a vast range of sound energy levels whereas our eyes will not actually see ripples of less than, say 5% of the original amplitude.
 

1. Why does the ripple effect occur on water but not on air?

The ripple effect is caused by a disturbance or displacement of the medium, which causes the medium to move in a circular motion. Water molecules are densely packed and can easily transfer energy from one molecule to another, resulting in the ripple effect. On the other hand, air molecules are more spread out and have less interaction with each other, making it more difficult for a disturbance to cause a ripple effect.

2. Can any medium exhibit the ripple effect?

Yes, any medium that is capable of transmitting waves can exhibit the ripple effect. This includes both liquid and solid mediums, such as water, sand, and even a drum skin. However, the appearance and behavior of the ripple effect may vary depending on the properties of the medium.

3. Why do ripples on water have a circular pattern?

The circular pattern of ripples on water is due to the surface tension of water. As the disturbance travels through the water, the molecules at the surface are pulled down by gravity, causing the wave to spread out in a circle.

4. Is it possible for the ripple effect to occur on air under certain conditions?

Yes, the ripple effect can occur on air under certain conditions, such as when the air is very dense or when a large amount of force is applied. For example, a sonic boom, which is caused by a supersonic object breaking the sound barrier, can create a ripple effect on the surrounding air.

5. How does the ripple effect on water differ from the ripple effect on air?

The main difference between the ripple effect on water and air is the medium's density and the molecules' ability to interact with each other. Water molecules are tightly packed and can easily transfer energy, resulting in a more pronounced ripple effect. Air molecules, on the other hand, are more spread out and have less interaction, leading to a less prominent ripple effect. Additionally, the ripple effect on water is two-dimensional, while the ripple effect on air is three-dimensional.

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