Waves - Matter is transported or not?

In summary, the discussion is about waves in class and whether matter is transported during a wave or not. The reading stated that matter is not transported, but the example of waves in the ocean does not necessarily prove this. There is a "loophole" when the water gets shallow and the speed of the waves decreases, causing the water to move towards the land. However, this is not a net movement and the original statement about waves not transporting matter still holds true. Teachers and textbook writers often simplify scientific facts and do not mention certain limitations. Water waves can still move matter, but the majority of the motion in the ocean is vertical. The theory of surface waves explains this vertical motion, and any horizontal movement quickly disperses. The statement
  • #1
tcharbuck31
3
0
Waves -- Matter is transported or not?

We are talking about waves in class. It stated in the reading that matter is not transported during a wave. However, water in the middle of the ocean is not proof that waves do not move matter, because even if waves do move matter, gravity would pull the water to the lowest possible point, evening the surface and returning water to the middle of the ocean.
Am I right or wrong?
 
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  • #2


What is the context of the discussion - electromagnetic (such as light or radio) or water or sound?

Water waves - things move around, such as waves on a beach or tsunamis.
 
  • #3


tcharbuck31 said:
We are talking about waves in class. It stated in the reading that matter is not transported during a wave. However, water in the middle of the ocean is not proof that waves do not move matter, because even if waves do move matter, gravity would pull the water to the lowest possible point, evening the surface and returning water to the middle of the ocean.
Am I right or wrong?

Water waves are a difficult type of wave to study as a start because they are a combination of transverse and longitudinal waves. I would be easier to discuss sound or waves on strings. However. . . . .
As you say, in the middle of the ocean, it is clear that nothing actually has a net movement in any direction - a floating ball just goes up and down and forwards and backwards in a circular motion. But there appears to be a 'loophole' in that statement about no transport of matter when the water nears the land. However . . .
When the water gets shallow, the speed of the waves gets less and the crests tend to fall over (break) because they overtake the troughs. The wave loses its shape and it is true that sometimes a beach ball can be pushed in towards the beach. BUT the water itself only ever gets so far up the beach (apart from the tide, which tends to cloud the issue in the sea). It's thrown forward but drains back - so there is still no net movement of the water - even though there is a lot of forward /backwards movement. So that basic initial statement about waves is still true.
 
  • #4


Meh, teachers and textbook writers get too overzealous when they try to convey these science "facts" that they don't say that they are only true in a certain limiting case. Water waves certainly can move matter... it's just that most of the wave motion in the ocean is up-down.
 
  • #5


Khashishi said:
Meh, teachers and textbook writers get too overzealous when they try to convey these science "facts" that they don't say that they are only true in a certain limiting case. Water waves certainly can move matter... it's just that most of the wave motion in the ocean is up-down.
Look at the theory of surface waves. The motion is in a vertical circle and not up and down.
It is true that you can launch a wave by 'pushing forward' and there is a flow of water 'away' but this disperses rapidly (DC is restored) and there is no forward flow. If there were then the logic tells us that there would be a build up of water at one side (or the other, or both sides, possibly) of the sea. Is there evidence of this? What goes on in the 'near field' is not included in this, of course because we would be dealing with the interaction of a wave with a structure of some sort, not just a wave.

But the statement in textbooks is not actually about "moving matter", as in 'pushing things'. It refers to movement of the actual medium. As I wrote earlier, water (surface) waves are not the best examples for an elementary discussion because the wave is more complex than most other wave motions.
 

1. What is a wave?

A wave is a disturbance that travels through a medium, transferring energy from one point to another without actually transporting matter.

2. How are waves created?

Waves can be created through a variety of mechanisms, such as vibrations, oscillations, or disturbances in a medium. For example, sound waves are created by vibrations in the air, while ocean waves are created by wind disturbances on the surface of the water.

3. Can waves transport matter?

No, waves do not transport matter. They only transfer energy from one point to another. For example, when a sound wave travels through the air, it does not physically move the air particles, but rather causes them to vibrate and transfer the sound energy.

4. What is the difference between mechanical waves and electromagnetic waves?

Mechanical waves require a medium to travel through, while electromagnetic waves can travel through a vacuum (empty space) without a medium. This is because mechanical waves rely on the physical displacement of matter, while electromagnetic waves are made up of oscillating electric and magnetic fields.

5. How does the frequency of a wave affect its energy?

The frequency of a wave is directly proportional to its energy. This means that as the frequency of a wave increases, so does its energy. This relationship is described by the wave equation, E=hf, where E is energy, h is Planck's constant, and f is frequency.

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