How are all of these comments ridiculous? Don't get me wrong, they're hilarious, but this is such a fascinating topic, and deserves more respect.

cuz some people are just bored.

what causes the color to move?

The frequency of waves. Like how many waves a second. For example, low frequency would affect the color (blue, red, yellow). Like this wave: ~~~~. A more frequent wave is this: /\/\/\/\/\/\/\. That will affect the color a bit different.

you should be able to see a light wave because it waves are you :)

You can't because the visible light we see has wavelengths of 400-700 nanometers, which our eyes can not see.

How does frequency work in real life?

frequency actually doesnt come in waves as shown in the videos but actually is shaped more like curve lines expanding outwards exponentially and nets when stacked. the light also fades and becomes dimmer the more the light expands.( the longer the distance between the light source and the object, the more the light waves expands)

idk maybe because colors are a relaxing thing to the human brain and when the colors brightness or exposure increases it is not a very relaxing thing to the human brain :)

Why is air consider a matter?

Because air has particles in it.

Why can EM waves travel through a vacuum but not mechanical waves?

Because vacuums have no mater and Mechanical waves need matte to travel to a point.

what is a mechanical wave

In physics, a mechanical wave is a wave that is an oscillation of matter, and therefore transferes energy through a medium.While waves can move over long distances, the movement of the medium of transmission—the material—is limited. Therefore, the oscillating material does not move far from its initial equilibrium position. Mechanical waves can be produced only in media which possess elasticity and inertia. There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves. Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves. Like all waves, mechanical waves transport energy. This energy propagates in the same direction as the wave. A wave requires an initial energy input; once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.

Main content

Course: Middle school physics - NGSS > Unit 4

Lesson 2: Mechanical waves and light

Mechanical waves and light

Google Classroom

Review your understanding of mechanical waves and light in this free article aligned to NGSS standards.

Key points:

Some waves can only travel through a material, or medium, such as air or water. These are called mechanical waves.
- Sound waves, water waves, and seismic waves are all types of mechanical waves.
Other waves, called electromagnetic waves can travel through a medium or through a vacuum where there is no matter, such as outer space.
- Light is a form of electromagnetic wave.
The amplitude and frequency of both mechanical and electromagnetic waves affect how we experience them.
- A light wave’s amplitude determines how intense, or bright, it is. Its frequency determines the light wave’s color.
- A sound wave’s amplitude determines how loud it is. Its frequency determines the sound wave’s pitch.

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aydgra4416
Posted a year ago. Direct link to aydgra4416's post “what causes the color to ...”
what causes the color to move?
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(18 votes)
Answer
- Sansdacomic
  Posted a year ago. Direct link to Sansdacomic's post “The frequency of waves. L...”
  The frequency of waves. Like how many waves a second. For example, low frequency would affect the color (blue, red, yellow). Like this wave: ~~~~. A more frequent wave is this: /\/\/\/\/\/\/\. That will affect the color a bit different.
  Comment on Sansdacomic's post “The frequency of waves. L...”
  (46 votes)
W
Posted a year ago. Direct link to W's post “How are all of these comm...”
How are all of these comments ridiculous? Don't get me wrong, they're hilarious, but this is such a fascinating topic, and deserves more respect.
Button navigates to signup pageComment on W's post “How are all of these comm...”
(22 votes)
Answer
- meizi.tan89
  Posted 5 months ago. Direct link to meizi.tan89's post “cuz some people are just ...”
  cuz some people are just bored.
  Comment on meizi.tan89's post “cuz some people are just ...”
  (16 votes)
patrick.aoun001
Posted 10 months ago. Direct link to patrick.aoun001's post “you should be able to see...”
you should be able to see a light wave because it waves are you :)
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(11 votes)
Answer
- IDK
  Posted 5 months ago. Direct link to IDK's post “You can't because the vis...”
  You can't because the visible light we see has wavelengths of 400-700 nanometers, which our eyes can not see.
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  (5 votes)
clara stowe
Posted a year ago. Direct link to clara stowe's post “what is a mechanical wave”
what is a mechanical wave
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(2 votes)
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- Ballet4ever
  Posted 9 months ago. Direct link to Ballet4ever's post “In physics, a mechanical ...”
  In physics, a mechanical wave is a wave that is an oscillation of matter, and therefore transferes energy through a medium.While waves can move over long distances, the movement of the medium of transmission—the material—is limited. Therefore, the oscillating material does not move far from its initial equilibrium position. Mechanical waves can be produced only in media which possess elasticity and inertia. There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves. Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves.
  
  Like all waves, mechanical waves transport energy. This energy propagates in the same direction as the wave. A wave requires an initial energy input; once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
  Comment on Ballet4ever's post “In physics, a mechanical ...”
  (14 votes)
NatalieP
Posted a year ago. Direct link to NatalieP's post “why colors”
why colors
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(3 votes)
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- Bhavika Ranjan
  Posted 10 months ago. Direct link to Bhavika Ranjan's post “idk maybe because colors ...”
  idk maybe because colors are a relaxing thing to the human brain and when the colors brightness or exposure increases it is not a very relaxing thing to the human brain :)
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  (9 votes)
Jose R
Posted a year ago. Direct link to Jose R's post “How does frequency work i...”
How does frequency work in real life?
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(7 votes)
Answer
- meizi.tan89
  Posted 5 months ago. Direct link to meizi.tan89's post “frequency actually doesnt...”
  frequency actually doesnt come in waves as shown in the videos but actually is shaped more like curve lines expanding outwards exponentially and nets when stacked. the light also fades and becomes dimmer the more the light expands.( the longer the distance between the light source and the object, the more the light waves expands)
  Button navigates to signup page
  (1 vote)
bcaskins
Posted a year ago. Direct link to bcaskins's post “What is frequency?”
What is frequency?
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(3 votes)
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- MICHAELB
  Posted a year ago. Direct link to MICHAELB's post “Wave cycles per second”
  Wave cycles per second
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  (5 votes)
bella
Posted a year ago. Direct link to bella's post “How does frequency work i...”
How does frequency work in real life?
Button navigates to signup pageComment on bella's post “How does frequency work i...”
(5 votes)
Answer
- meizi.tan89
  Posted 5 months ago. Direct link to meizi.tan89's post “frequency actually doesnt...”
  frequency actually doesnt come in waves as shown in the videos but actually is shaped more like curve lines expanding outwards exponentially and nets when stacked. the light also fades and becomes dimmer the more the light expands.( the longer the distance between the light source and the object, the more the light waves expands)
  Button navigates to signup page
  (2 votes)
.
Posted 9 months ago. Direct link to .'s post “Why is air consider a mat...”
Why is air consider a matter?
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(3 votes)
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- QuantumTimeTraveller
  Posted 8 months ago. Direct link to QuantumTimeTraveller's post “Because air has particles...”
  Because air has particles in it.
  Comment on QuantumTimeTraveller's post “Because air has particles...”
  (6 votes)
Wowzers
Posted a year ago. Direct link to Wowzers's post “Why can EM waves travel t...”
Why can EM waves travel through a vacuum but not mechanical waves?
Button navigates to signup pageComment on Wowzers's post “Why can EM waves travel t...”
(3 votes)
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- minejava22
  Posted 9 months ago. Direct link to minejava22's post “Because vacuums have no m...”
  Because vacuums have no mater and Mechanical waves need matte to travel to a point.
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  (3 votes)