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In addition, although it is feasible to calculate the speed of light using this method, there may be some errors considering the rotation of the planet itself, and only an approximate value can be estimated.
"So we can only use the stupid method, such as repeating your original experiment again. If one kilometer is not enough, then try ten kilometers, or even a hundred kilometers!" Harov said firmly.
"In fact, there are already quite a few people preparing to do similar experiments. Their ideas are very interesting. Let's let them do it." Aurora shook her head. Since someone was helping her verify it, it would be nice to save some effort.
Chapter 319 It seems that the speed of light is not very fast
The next evening, in Greenriel City, thousands of wizards and civilians gathered outside a street, watching Glenn and his team hang smooth mirrors on every wall of the street...
"There are only fifty mirrors left. Place them according to the blueprint. The angles cannot be wrong at all!"
Glenn loudly instructed Nancy and others to put the mirrors in the appropriate places and adjust the angles according to his precise calculations.
Thanks to the wizard's steady hands and high precision, if the angle was fifteen degrees, it would never be sixteen degrees, otherwise it would not be easy to connect the reflected light from hundreds of mirrors.
Just to calculate the various angles of refraction, it took the seven wizards a whole day!
What made Green feel a little relieved was that the process of borrowing the mirror was very smooth. After knowing that it would be used for the speed of light measurement experiment, many curious wizards generously contributed the round mirrors they had bought before.
He even got permission from the council to use Greenridge's streets and squares for his experiments when the sun went down and the shops closed.
It took Glenn and his team more than an hour to place the last fifty mirrors. By the time they finished, the sun had set and the entire city of Greenrill was in darkness.
At his request, there were no candles in any of the houses, and everyone could only see the things around them with the help of a little moonlight.
"Glenn, can you speak now? Why do you want to borrow so many mirrors from us? Are you planning to use this to measure the speed of light?" A wizard who was familiar with Green asked impatiently.
Everyone present also had an expectant expression. Due to the temptation brought by the Silver Moon Medal, there were many wizards who wanted to complete this experiment. There were all kinds of ideas, but Glenn was the first person to put his ideas into action!
Facing the gazes of the crowd, Glenn seemed a little nervous, but he still spoke nonstop. "My plan is to use the principle that mirrors can reflect light to increase the distance traveled by light, so as to measure the speed of light..."
He placed a large number of mirrors in Greenrail City, and in a moment, he would create a beam of strong light that would be reflected from the gate of East City District to West City District, then to South City District, and then return in a circle...
"It requires a total of one thousand reflections and a total distance of one hundred kilometers!" Glenn said proudly.
He had calculated every point where the mirrors were placed precisely, which meant that they only needed to stand still and wait for the light to circle around Greenrail City, and the final landing point would be the tower above their heads!
"I placed a piece of white cloth on the top of the tower. Whenever you see a conspicuous spot of light on it, it means that the light has turned back once and traveled a distance of 100 kilometers. You can use the time it took to calculate the speed of light by reverse calculation..." Glenn explained.
"What a novel idea, it can be done this way..." Raphael suddenly realized and looked at the wizard named Glenn with admiration. In this way, only a few streets are needed to create a distance of 100 kilometers and conduct experiments under their noses.
The other wizards immediately became interested. Glenn's plan sounded feasible. It was a full 100 kilometers. At least the light element would need one or two seconds to run, right?
"Dean Lin, do you think this can measure the speed of light?" Alok couldn't help but ask. He knew that the dean was also preparing for related experiments recently, which would determine the ownership of a Silver Moon Medal.
"It's feasible, but it's also not feasible..." Lin En smiled and spoke mysteriously, with no intention of revealing the answer.
I have to say Glenn is quite creative. He even thought of this method, but he still lacks some considerations...
Seeing that Lin En's words were so ambiguous, the wizards on the field couldn't help but curl their lips. It seemed that even this magic star didn't know the result and could only use this excuse to save face.
But that's true. If the other party knew it in advance, they would have measured the speed of light long ago... After all, this experiment is not complicated. As long as there are enough mirrors, the experiment can be easily replicated.
Glenn did not argue with the crowd. He took the blueprint in his hand and checked it one last time. He took a deep breath and adjusted his state.
Time passed bit by bit, and when there were about three seconds left until midnight, Glenn raised his hand, and a scorching fireball appeared in the air, illuminating the entire street.
But this was just the beginning. Glenn and five other wizards cast a spell together. As the magic power surged, circles of reflective layers began to appear around the fireball, forming a closed sphere in mid-air, enveloping the fireball, leaving only a small hole with a diameter of one centimeter...
The light released by the entire fireball was gathered together and shot out through the small hole, aiming at the first circular mirror.
Glenn controlled the time extremely accurately. It was the moment when the magic clock reached zero. Under the attention of countless people, dazzling beams of light appeared in the entire street, and under the continuous reflection of the mirror, they stretched to the end of the field of vision.
Nancy stood with her back to Glenn, staring at the top of the tower, not daring to blink for fear of missing the light. She held a magic clock in her hand, and she had to stop it immediately the moment she saw the light. The final time was the time it took for light to travel one hundred kilometers.
One second... three seconds... five seconds... ten seconds...
Nancy stared so hard that her eyes were almost sore, but there was nothing on the white cloth on the tower, and no light appeared.
"It seems that the speed of light is not very fast... It's been more than ten seconds, why hasn't it arrived yet?" Alok muttered.
"That's a full 100 kilometers. Even if you run as fast as you can, it'll take you half a minute, right?" Pierce said with a smile.
Raphael and others frowned, and a thought vaguely emerged in their minds: could there be something wrong with the experiment?
Thinking of this, several great wizards flew up directly, intending to look around the entire city from high in the sky to find out where the problem lies.
Glenn below also noticed something was wrong, because the light intensity from the mirrors he saw was decreasing much faster than he expected...
About ten seconds later, Raphael and others returned from the air, and their expressions became somewhat helpless.
"Master Raphael, what's the situation? Is the light not here yet?" One of Glenn's good friends came forward and asked curiously.
Chapter 320: A big deal... A vacuum area covering half the city!
The first words Raphael said after returning to the ground from the air stunned everyone present.
"I'm afraid it will be difficult to continue this experiment!"
"Master, what's going on? Could it be that the refraction angle of the light is wrong?" Nancy asked anxiously. However, they had confirmed dozens of times that every mirror was carefully placed according to the blueprint.
But before Raphael could answer, Glenn sighed and said, "Maybe the light has become weaker?"
"That's right!" Raphael nodded. "I just checked in the air. The light beam you created has become so weak that it cannot be recognized by the naked eye after being reflected by the seventy-third mirror..."
"It's decaying so quickly?!" Glenn's face turned pale. If the light could penetrate three or four hundred mirrors, there might be a way to make up for it. All he needed to do was find a few more wizards to cast spells together and create a more powerful light beam.
But there are only seventy-three mirrors, and they only cover one-fourteenth of the distance. With such an attenuation frequency, they have to strengthen the light beam ten times or even a hundred times?
How is this possible?
"Master Lin En, I think you should know what's going on?" Raphael turned to look at Lin En and asked.
Everyone present turned their eyes to the Magic Star and immediately remembered Lynn's comments on the experiment.
Possible, but not feasible...
Lin En didn't keep the secret any longer and started to explain. "It is possible to use the principle of reflection to make light travel a longer distance. However, although the mirror can reflect light, it cannot reflect it completely. It will inevitably lose some energy every time..."
"In other words, we should reduce the number of mirrors and increase the distance of each reflection?" A wizard quickly thought of a solution.
"No, that won't work at all," Glenn sighed. "Light can't travel very far."
He had already tried this before, so he reduced the distance between the two mirrors to about a hundred meters.
"That's because the elements in the air also reflect and absorb light, and the light itself does not propagate in parallel, but diffuses in all directions, so we can see the light..." Lynn continued to explain.
In other words, as long as they can see the light, it means that the light is dispersed and reflected into their eyes... Raphael immediately understood what Lin En meant, but then suddenly retorted.
"This shouldn't be right. Then how can the sun's light travel thousands of kilometers to reach this eternal star?"
After Raphael's reminder, many wizards also discovered the "loophole" in Lin's words. If the light is constantly attenuating, then the light from the sun cannot reach here!
The wizards of the School of Prophecy have calculated the distance between the Eternal Star and the Sun. It is an extremely astonishing number. Even the nearest point is over 100 million kilometers away!
"Outside our planet, in the vast universe, the content of elements is very rare, and light does not lose energy in a vacuum. As for after reaching this planet, it is only scattered and absorbed by the elements, not disappeared..." Lin En shook his head and said.
Lynn's answer dispelled everyone's doubts, but the series of problems left Glenn and others completely stunned.
In this case, the problem of light intensity attenuating with distance cannot be solved. Glenn thought hard for a while, but he couldn't think of how to make the light cross a distance of 100 kilometers and still be seen by them...
Is it possible that we can only declare failure?
Glenn was very unwilling to accept this. He had made so many preparations and put on such a big show, but in the end he still failed...
It is conceivable that they will become the laughing stock of wizards' gossip tomorrow.
At this moment, a voice like a loud bell suddenly rang in everyone's ears. "Then why don't we make these troublesome elements disappear, create a large enough vacuum area, and simulate the environment of the universe?"
Everyone present looked in the direction where the voice came from, and then found that several legendary Speakers were walking towards them, and the one who spoke was Harov!
"Lord Harof!" Glenn was surprised.
Yes, as long as we create a vacuum area that covers the distance that light propagates, we can greatly reduce the degree of reduction in light intensity.
Only a legendary wizard like Harof could come up with this outrageous, yet very effective solution!
After Harrof spoke, the wizards gathered nearby also offered advice to Glenn.
For example, a thousand mirrors are really too many. They can simply increase the distance of each reflection by one kilometer, so only a hundred mirrors will be enough!
Even Anthony stood up. He was very interested in this experiment of measuring the speed of light with a mirror, and he took the initiative to suggest that he could use thunder magic to create a more powerful light source...
Amid the lively discussions among the crowd, one problem after another was solved. Such an enthusiastic magic research atmosphere also made Lin En feel very comfortable.
Although there were many people on the scene who were just watching the fun or even waiting to see the joke, there were also many wizards who were concentrating on magic research and wanted to figure out how fast the speed of light was.
Glenn also cheered up and modified the position and angle of each mirror on the drawing. He reduced the number to one hundred and prepared to do another experiment with the help of more powerful light!
"All irrelevant people please stay away first, and all great wizards please stay!" Harof said solemnly. Even if he was a legend, he could not repel elements on such a large scale, and he had to gather everyone's strength.
The preparations took another hour to complete.
Anthony took the lead. Flashes of lightning began to appear in his palms, and they became brighter and brighter. The violent thunder continued to leap. Both civilians and wizards squinted their eyes. The light was so bright that it was impossible to look directly at it...
"Let's start!" Harrov raised his voice a little, and his voice spread to every corner of the city.
At the same time, twenty great wizards and three legends cast spells together. The elements that kept surging around them were quickly repelled under the influence of huge magic power. In just three seconds, a vacuum field covering half of the city had quietly taken shape!
"What a grand deal..." Lin En said with emotion. The wizards' imagination and practical ability far exceeded his expectations, but he quickly gathered his thoughts, raised his hands to specifically expand his own territory, and completed the vacuum section that he was responsible for.
Chapter 321 A beam of light cuts through the sky!
After the vacuum field was gradually formed, Glenn once again released his focusing magic, and the flashing electric ball suspended in the air was wrapped up.
A beam of light so strong that it was difficult to look directly at shot out from the tiny hole. However, since there was no element in a vacuum to reflect light, the people present could not see the beam at all. They could only determine the trajectory of the light by the one hundred circular mirrors that lit up in the Wizard City.
“It appeared, it appeared!”
The wizards waiting outside the vacuum field looked at the top of the tower in amazement. Although the incomplete reflection of the mirror would attenuate the intensity of light layer by layer, this time the light did not disappear after traveling a full hundred kilometers, but instead illuminated the top of the tower and the entire white cloth.
"Did you see when it arrived?" Pierce asked curiously. He just blinked and didn't see clearly when the light reached the top of the tower.
"It seems like just a moment? It was too fast..." Alok shook his head. He didn't even blink just now and couldn't see clearly.
The vacuum area covering half of the city slowly faded away. Maintaining such a huge area was not an easy task even for great wizards and legendary wizards.