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# Waves Watch

1. Nodes carry no energy

can someone explain this to me?
2. Infact, i might be able to
The nodes are the points on the wave with the least amplitude. This means they have the least displacement and therefore they have the least energy.
On the other hand, anti nodes have the most amplitude, and therefore carry the most energy
Spoiler:
Show
This shows the nodes and antinodes on the wave, the nodes always have the least amplitude (usually 0) and therefore have no movement, no movement is no kinetic energy etc.
3. (Original post by The-Spartan)
Infact, i might be able to
The nodes are the points on the wave with the least amplitude. This means they have the least displacement and therefore they have the least energy.
On the other hand, anti nodes have the most amplitude, and therefore carry the most amplitude
Spoiler:
Show
This shows the nodes and antinodes on the wave, the nodes always have the least amplitude (usually 0) and therefore have no movement, no movement is no kinetic energy etc.
where does this come from? i understand the least displacement and amplitude but i don't see where energy comes into this.

is there an equation which explains this?
4. (Original post by thefatone)
where does this come from? i understand the least displacement and amplitude but i don't see where energy comes into this.

is there an equation which explains this?
Ke=1/2 mv^2. Therefore if the rope isn't moving (which is the case of a node) the kinetic energy of the wave at that point is 0 as the velocity is 0
5. (Original post by samb1234)
Ke=1/2 mv^2. Therefore if the rope isn't moving (which is the case of a node) the kinetic energy of the wave at that point is 0 as the velocity is 0
do waves have kinetic energy????
6. (Original post by thefatone)
do waves have kinetic energy????
Yes
7. (Original post by samb1234)
Yes
how???? i understand the particle nature of the em spectrum as demonstrated by the photoelectric effect but how to waves transfer energy?
8. (Original post by thefatone)
how???? i understand the particle nature of the em spectrum as demonstrated by the photoelectric effect but how to waves transfer energy?
Well the string is moving right? therefore if it is moving it must have a kinetic energy. The derivation of the exact energy of a wave goes way beyond this level
9. (Original post by thefatone)
how???? i understand the particle nature of the em spectrum as demonstrated by the photoelectric effect but how to waves transfer energy?
Em waves don't have kinetic energy. Waves like sound waves do.
10. (Original post by samb1234)
Well the string is moving right? therefore if it is moving it must have a kinetic energy. The derivation of the exact energy of a wave goes way beyond this level
the string is a materialistic thing whereas a wave is not
11. (Original post by thefatone)
the string is a materialistic thing whereas a wave is not
Certain waves involve displacing matter. E.g. a wave in water, the water has energy from this wave like motion. In the circumstance of a wave in water the higher the displacement then the more EK there is.
12. (Original post by thefatone)
the string is a materialistic thing whereas a wave is not
The wave is travelling through the string
13. (Original post by Vikingninja)
Certain waves involve displacing matter. E.g. a wave in water, the water has energy from this wave like motion. In the circumstance of a wave in water the higher the displacement then the more EK there is.
I see so the waves transfer energy by displacing other stuff? so would those be classed as mechanical/longitudinal waves?
(Original post by samb1234)
The wave is travelling through the string
yes thus the wave isn't materialistic, yes it acts through the string
14. (Original post by thefatone)
I see so the waves transfer energy by displacing other stuff? so would those be classed as mechanical/longitudinal waves?

yes thus the wave isn't materialistic, yes it acts through the string
A mechanical wave is where matter is oscillating so yes, a EM wave wouldn't be this. Mechanical waves can be transverse or longitudinal. Example of transverse is a water ripple/wave and a longitudinal one would be a sound wave. A sound wave works by knocking particles into each other and transferring their EK.
15. (Original post by Vikingninja)
A mechanical wave is where matter is oscillating so yes, a EM wave wouldn't be this. Mechanical waves can be transverse or longitudinal. Example of transverse is a water ripple/wave and a longitudinal one would be a sound wave. A sound wave works by knocking particles into each other and transferring their EK.
water waves aren't a great example for this, they are a combination of both which might confuse things further
16. (Original post by Vikingninja)
A mechanical wave is where matter is oscillating so yes, a EM wave wouldn't be this. Mechanical waves can be transverse or longitudinal. Example of transverse is a water ripple/wave and a longitudinal one would be a sound wave. A sound wave works by knocking particles into each other and transferring their EK.
i guess what i'm really asking is how this happens... which is probably way beyond my level. ;(
17. (Original post by thefatone)
i guess what i'm really asking is how this happens... which is probably way beyond my level. ;(
This gif shows how they knock into each other and rebound.

In a collision between two particles, EK is transferred.
18. (Original post by Vikingninja)
This gif shows how they knock into each other and rebound.

In a collision between two particles, EK is transferred.
i see ok thanks at leats there's 1 thing i understood.....

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