Chapter 23 Colorful Light


Chapter 23 Colorful Light

Friends who have studied physics should all know this.

The refractive index of visible light varies in different environments, such as glass, air, water, etc.

These things have a unified conceptual name, which is medium.

Nowadays, as the theoretical research of optics is gradually standardized, many junior high school students will also understand a truth:

Light can propagate in a medium, and the propagation of light itself does not require a medium.

But don’t forget, Mavericks was in 1665, a period when optical research was still in its infancy.

Therefore, with just a few words from Xu Yun, Xiao Niu came up with the idea of ​​seven-color light having different effects in different media in less than half a minute. This is a completely super level performance.

True.

The current Mavericks do not yet know that light itself is a boson and does not need to be propagated with the help of any fermions - in this era, the top optical theory of refraction is a mathematical equivalent form derived by Snell, and in his No one knew before his death.

It would be after Huygens and others reviewed his manuscript in 1678 that it would be published as the famous Snell's law.

Prior to this, the equivalent equation had only been derived by Descartes in "Refraction".

And there is a very confusing matter that no one can tell the truth about, so now they are still sharing the honor of discovering the law of refraction of light.

Therefore, although Mavericks' statement subconsciously covers the speculation that visible light cannot be transmitted through a certain 'environment', this is a completely understandable situation - to be honest, can you imagine that the previous layer has already exploded?

Then looking at the small cluster of colorful lights on the ground, Maverick suddenly thought of something.

He thought for a few seconds and asked Xu Yun:

"Fat Fish, since sunlight can be dispersed into seven beams of colored light, are these seven colored lights different lights?

Also, theoretically, these seven beams of light should be able to be recombined into one beam of white light, right? ”

Xu Yun twitched the corners of his mouth. Hey, opening his mouth revealed two more fatal points.

However, at this time, he had gradually adapted to the perverted thinking ability of this patriarch, so he quickly adjusted his mentality and said:

"Sorry, Mr. Newton, I only know the answer to the last question - as long as the conditions are right, the seven-colored light can be reunited into a beam of white light."

Mavericks was already interested at this time, and his eyes rolled:

"Fat Fish, you just said that a prism can also verify the dispersion phenomenon?"

"Yes, and the effect of prisms is much better than lenses."

Maverick nodded slightly, but soon his brows wrinkled again:

"A prism? It's easy to find this thing in London. You can buy it in any optical shop on the street, but here in Woolsthorpe."

Looking at the frowning Mavericks, Xu Yun took out a prism from his pocket as if by magic:

"Mr. Newton, look what this is?"

Mavericks took it and took a look:

"Eh? Why do you have a prism?"

Xu Yun smiled and said nothing.

The price of prism pendants in later generations was so low that many people liked to buy them as keys or even necklace ornaments. Xu Yun took an optical course last semester and bought a prism pendant. On the key ring.

More than ten minutes later.

A table about one meter in diameter, a prism and a black wooden board were placed next to the water tank.

Xu Yun then stood up the prism, adjusted the angle skillfully, and made an OK gesture towards Mavericks.

After a while.

Sure enough, a cluster of long spectra appeared on the cardboard behind the prism, and it was much clearer than the previous cluster.

Upon seeing this, Xu Yun stepped aside, deliberately not making any expression, wanting to see what the youth version of the Patriarch could do without any prompting.

I saw Maverick walking to the table, and took a closer look at the spectrum.

Then he hesitated for a few seconds and picked up a piece of black cardboard.

Cut out a circle on it and place it on the outside of the prism, which is the direction from which the light source comes.

A large amount of sunlight was blocked by the cardboard, and only a circular beam of light came in through the small hole, and then.

A long spectrum was still formed.

Seeing this, little Newton said softly "Hey".

Not sure if it was because he wanted to talk to someone, but he suddenly looked at Xu Yun again:

"Fat Fish, have you heard of Mr. Descartes' theory?"

Xu Yun nodded and said:

"Of course I have heard of it. I visited the University of Poitiers once.

Mr. Descartes believed that the color of light comes from the medium between the luminous body and the human eye, and has nothing to do with the light source.

The color of light is not a characteristic of light itself, and the theory of light trace transformation was also proposed. ”

"That's good, but look here."

Maverick held the cardboard in one hand and pointed at the projected long spectrum with the other hand:

"According to Mr. Snell's equation and Mr. Descartes's theory, a circular light beam should form a circular or elliptical light spot after passing through a prism.

But after dispersion occurs, the colorful light forms a long spectrum.

Could it be said.

Is there something wrong with Mr. Descartes’ theory? ”

After Mavericks thought for a while, before Xu Yun answered, he picked up the cardboard and scissors again and made a smaller hole.

He placed the cardboard behind the first prism so that, using the circular hole, he could capture any beam of light in the band of colored light. (Mavericks originally hand-painted this device, (DOI) 10.1098/rsta.2014.0213, Mavericks’ own handwriting. If you are interested, you can take a look. He is really a soul painter)

Then Mavericks waved to Xu Yun and motioned for him to come forward:

"Fat Fish, I'll report the data, and you'll take the records."

Xu Yun's pupils shrank slightly, knowing that the calf was swimming towards his final "net" step by step, but his expression remained unchanged:

"Okay, Mr. Newton."

Then one of the two took a pen and paper, and the other began to calculate the angle.

"Red light, incident angle i60°, deflection angle β32.2°"

"Orange light, incident angle i60°, deflection angle β37.4°"

"Incidence angle i60°, deflection angle β38.7°"

After 20 minutes, the data of four groups and 28 times were recorded.

Different types of light have different refractive indexes in optical glass. The underlying reasons involve the relative magnetic permeability μr and the relative dielectric constant εr. These two constants require the calculation of Maxwell's equations in the medium, and then establish an intuitive relationship between matter and light. Interaction model, summarize the equation of motion through linear dissipative force, and then use the complex number method to solve its steady state, etc.

However, considering that it is not yet on the shelves and is inconvenient for PUA readers. Ahem, the content is too complicated. Everyone only needs to understand the relevant conclusions from a macro perspective.

After all, there was no Maxwell’s equations in Mavericks’ era, right?

"Purple light 1.532 blue 1.528 green 1.519 yellow 1.517 orange 1.514 red 1.513"

Looking at the fixed sets of data in front of him, Mavericks couldn't help but take a deep breath.

It's obvious.

The refractive index of different colors of light is different and remains constant. The properties of these seven colors of light are different.

From this we can draw a conclusion:

White light is indeed not pure light, it is made up of different lights.

And this means

He may be one step closer to the truth of the world.

at the same time.

Maverick looked at this light that was divided into seven and merged into one at the same time, and something suddenly came to his mind.

I saw his chest suddenly rise and fall a few times, and he quickly ran back to the house. (End of chapter)

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