What is the exact definition of a wave?

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The discussion centers on defining a wave, highlighting that it is generally understood as a disturbance that carries energy through space and time without permanently displacing particles. Key properties of waves include reflection, refraction, polarization, interference, and diffraction, which help distinguish them from other phenomena. The conversation acknowledges the complexity of defining waves due to their varied contexts, such as standing waves and different types like transverse and longitudinal waves. Examples provided include ocean waves and sound waves, illustrating the concept's application in different mediums. Ultimately, the definition of a wave remains nuanced and context-dependent, emphasizing its role as a propagating disturbance.
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I know it when I see it but what is the exact definition of a wave? what makes a wave a wave?
 
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you call that exact? that's little better than 'I know it when I see it'.
 
The textbook definition is something like "A propagating disturbance that carries energy".

What makes a wave really a wave would be its wave properties.
All waves experience the following under certain conditions:

Reflection, refraction, polarisation, interference and superposition and diffraction.
 
http://www.mathlinks.ro/viewtopic.php?p=1096064#1096064 is what i think of waves as
 
jtbell said:
To me, a wave is a motion that satisfies the differential wave equation.

Hmm, this won't work for nonlinear waves or the Schroedinger equation.

jaseh86 said:
The textbook definition is something like "A propagating disturbance that carries energy".

This doesn't work for standing waves.

jaseh86 said:
All waves experience the following under certain conditions:

Reflection, refraction, polarisation, interference and superposition and diffraction.

Interference is my personal favourite - Young's double slit is so signature! But is it defined when superposition doesn't hold?

granpa said:
I know it when I see it

kateman said:
"# one of a series of ridges that moves across the surface of a liquid (especially across a large body of water)
# a movement like that of a sudden occurrence or increase in a specified phenomenon; "a wave of settlers"; "troops advancing in waves"
# (physics) a movement up and down or back and forth"

So maybe these definitions are still the best?
 
A standing wave is still considered a disturbance in space-time right?

How about wave = "a disturbance...in the force"
 
My personal favorite is a cold snap, the inverse of a heat wave.

Odd that it's so hard to pin down. A string can support reflection if the mass density of the string changes, but as a one dimensional wave, diffraction and refraction are out.
 
  • #10
I think the word "wave" is heavily overloaded with meanings, definitions and all that, and it depends on the context what is exactly meant by it. However, within many contexts, an exact definition can be given, and there are some similarities to them over all these classes, which comes down to "stuff that wobbles in space and time".
 
  • #13
Wave is a simple harmonic motion which carries energy and information through an object but do not move object's particles..
 
  • #14
granpa said:
what makes a wave a wave?

Within an antenna context, a wave describes the instantaneous energy passing through a closed surface containing the radiator. Usually, the closed surface is defined as a sphere for simplicity (since all points on the surface are equidistant from a single reference point - the phase center).

For extended objects (where the smallest sphere that completely contains the radiator is many wavelengths in diameter), the instantaneous energy distribution on that closed sperical surface can be anything but simple (although it is merely a superposition many simple waves).

Regards,

Bill
 
  • #15
A wave is a disturbance that carries energy (not matter) from one point to another through a series of continuous movements.

There exists two types of waves : transverse and longitudinal waves.

The difference between the two is the way they carry the energy from one point to another.

A transverse wave transfers energy through series of upwards and downwards oscillations.

A longitudinal wave transfers energy through a series of compressions and rarefactions (expansions).

Some waves are a combination of both like water waves.

A good site to visit for clearer explanations on waves is:

http://www.kettering.edu/~drussell/Demos/waves/wavemotion.html"
 
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  • #16
Chaulesh said:
There exists two types of waves : transverse and longitudinal waves.

Spherical waves have both tangential and radial components, but the radial component tends toward zero as the radius increases beyond \frac{2 D^2}{\lambda}.

Regards,

Bill
 
  • #17
A wave is a disturbance that propagates through space and time, usually with transference of energy. Waves travel and transfer energy from one point to another, often with little or no permanent displacement of the particles of the medium instead there are oscillations around almost fixed locations.
Wave is
-A movement like that of a sudden occurrence or increase in a specified phenomenon.
-One of a series of ridges that moves across the surface of a liquid .

Examples of waves are:

Ocean surface waves, which are perturbations that propagate through water.
Sound — a mechanical wave that propagates through air, liquid or solids.
--------------
Richa
 
  • #18
A wave is not quite a thing (mass), but more than a thought (C squared)
 
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  • #19
A wave is not quite a thing (mass), but more than a thought (C squared)
 
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