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 avito009 Nov 27th 2017 02:16 AM

What did Newtons Prism experiments prove?

What did Newtons Prism experiments prove?

Did it prove:

1. Prism was not changing the color of light. This was proved when light was passed through a prism and very close to the original prism was placed another prism such that the refracted light from the first prism moved through the second prism and as it moved through second prism white light was produced. Proving that the prism was not changing the color of light.

2. Light is a particle. Since light after refraction through a prism moved in straight lines and waves dont travel in straight lines.

 avito009 Nov 27th 2017 02:57 AM

What proves light travels in a straight line?

Do shadows prove that light travels in a straight line? If so, How?

 HallsofIvy Nov 27th 2017 05:09 AM

The prism experiments certainly did NOT "prove that light is a particle". And wave do move in straight lines, as long as the they are not changed. For example, if a water wave passes over an area where one portion is shallower than the other, the wave will bend but if the water stays the same depth the wave "moves in a straight line. I don't know where you got the idea that they don't.

For you second question, imagine strings running from each point on the edge of a shadow to the corresponding point on the object casting the shadow. You will see a lot of parallel straight lines.

(Is this for a sixth or seventh grade science class?)

 benit13 Nov 27th 2017 05:58 AM

Quote:
 Originally Posted by avito009 (Post 38121) What did Newtons Prism experiments prove? Did it prove: 1. Prism was not changing the color of light. This was proved when light was passed through a prism and very close to the original prism was placed another prism such that the refracted light from the first prism moved through the second prism and as it moved through second prism white light was produced. Proving that the prism was not changing the color of light. 2. Light is a particle. Since light after refraction through a prism moved in straight lines and waves dont travel in straight lines.
1. Yes, this makes sense. It's part of the phenomenon he was studying, which is that white light is a mixture of light waves with different colours rather than its own colour.

2. Nope. You can get plane waves that do travel in a straight line. The 'photon' stuff came with the discovery of the photoelectric effect and the "ultraviolet catastrophe".

 Physbits981 Dec 4th 2017 02:27 PM

The waves and straight lines confusion is common (I have found) in lower school science. Children can accept that light travels in straight lines but only until they know it's a wave and then they think it must travel in wiggly lines.
I'm not sure what level the questions above were directed at though.

 avito009 Dec 10th 2017 05:51 AM

Corpuscular theory of light.

Newton tried to prove light is made up of particles from the prism experiment.

From Wikipedia:

"Isaac Newton argued that the geometric nature of reflection and refraction of light could only be explained if light was made of particles, referred to as corpuscles, because waves do not tend to travel in straight lines. Newton sought to disprove Christiaan Huygens' theory that light was made of waves. In his 44th trial in a series of experiments concerning physics of light, he concluded that light is made of particles and not waves by having passed a beam of white light through two prisms which were held at such an angle that the light split into a spectrum after passing through the first prism and then was recomposed, back into white light, by the second prism."

https://en.wikipedia.org/wiki/Corpus...heory_of_light

"Because waves do not tend to travel in straight lines."

 avito009 Dec 11th 2017 10:15 AM

Einstein or Newton?

It might seem reasonable to question at this point of time as to why Einstein is given full credit for proving that light is made up of particles with his photoelectric effect experiment when Newton already started the process with his prism experiments.

 Woody Dec 11th 2017 02:31 PM

I think that I would argue that light is neither a particle or a wave, even the term "wavicle" (which is sometimes used) is misleading, light is its own thing.

It has been found that in some circumstances the mathematical models pertaining to particles can be successfully applied to model its behaviour,
While under other circumstances the mathematical models pertaining to waves have to be used.

However it is not a particle or a wave, it is light and behaves like light.

 WriterWriter Dec 15th 2017 08:30 AM

Newton believed that all the colors he saw were in the sunlight shining into his room. He thought he then should be able to combine the colors of the spectrum and make the light white again. To test this, he placed another prism upside-down in front of the first prism. He was right. The band of colors combined again into white sunlight. Newton was the first to prove that white light is made up of all the colors that we can see

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