Chapter 161: Which sect is Bernoulli from?

Dongfang Bubai was stunned for a moment. Usually, her followers spoke to her with utmost sincerity and fear, and they didn’t even dare to lift their heads, but now she was actually spanked by Song Qingshu!

However, the anger in her heart was soon diluted by the surprise Sword Flight brought to her. Dongfang Bubai’s whole body was hanging on to Song Qingshu, and her eyes were wide open, as she looked at the blue sky, white clouds and the rapidly receding forest under her feet with the wonder of a newborn child. 

Although her movement technique was unparalleled in the world, she couldn’t fly freely in the sky like this.

“If you can take me to touch the cloud, I won’t care about your offense of… doing that.” Song Qingshu was trying to control the balance between the two, when he suddenly heard Dongfang Bubai’s voice in his ears. Looking up, he saw that she was extending her slender white fingers to point to a cloud not far away.

“What is there to touch about a mass of steam…” Song Qingshu grumbled, but still controlled the Wooden Sword to fly towards the cloud.

“I actually touched the cloud?” When Song Qingshu led her into the cloud, Dongfang Bubai seemed to feel as if it was a little unbelievable, her eyes were dazed, she reached out to touch it, but couldn’t catch anything. 

“It just feels wet, extraordinarily illusory. I always thought that clouds would be soft to the touch, like cotton candy…” Thinking of the reverie that occasionally occurred when looking up at the starry sky, Dongfang Bubai felt that she was stupid at that time.

Suddenly, she felt a huge movement, and was so frightened that she hooked her hands on Song Qingshu’s neck again, “What happened?”

At the moment, Song Qingshu was drenched in cold sweat and spoke through gritted teeth, “I’m afraid we’re going to… crash!”

As soon as his voice fell, the two fell straight down. Song Qingshu only felt that the True Qi in his body was going haywire, and his body felt both hot and cold.

He tried his best to control the speed of their descent and started to glide. But, he staggered and descended another several hundred meters. Song Qingshu couldn’t control it any longer, and the two fell directly towards the ground.

Fortunately, after this period of time, Dongfang Bubai had recovered some of her internal energy. At that point, their distance from the ground was not too high. She noticed that Song Qingshu’s True Qi was out of control, and quickly let go of her hands that were hooking his neck, and hugged him in her arms. She noticed that there was a pool of water below, and used her internal force to keep hitting the water with her palms, while using the rebound force to decrease the speed of their fall.

However, the force with which the two were falling was just too much. Feeling the rebound force from the water surface, Dongfang Bubai spit out a few mouthfuls of blood.

*****

Song Qingshu woke up from his unconscious state and found himself lying on a gravel mound. He heard the sound of water nearby, followed the sound, walked over, and found Dongfang Bubai sitting on a rock on the bank of a lake. She was lifting the hem of her dress, her pair of crystalline white calves soaked in water, there was a long and narrow wound on it, and blood was constantly seeping out from the wound. Dongfang Bubai was holding a handkerchief and gently wiping the blood around the wound.

The water surface was sparkling, and Song Qingshu couldn’t directly look at it, but he felt that the skin on Dongfang Bubai’s calf was more dazzling than the lake surface.

Dongfang Bubai quickly noticed his arrival, naturally lowered the hem of her dress, and stood up, “You are awake?”

“I’m really sorry that you suffered such a wound.” Song Qingshu glanced at her calf with a look of apology.

“What’s wrong with a little injury?” Dongfang Bubai shook her head indifferently, “You have given me enough surprises today. You have to tell me how to achieve Sword Flight.” Dongfang Bubai felt a little excited at the prospects of leisurely roaming the sky while riding the wind.

“I can tell you, but I’m afraid you won’t understand.” Song Qing hesitantly said.

Dongfang Bubai’s face froze when she heard him speak, “In the world of martial arts, even if I am not the number one practitioner, I am definitely in the top three, and you think I won’t understand?”

“Alright, listen carefully…” Song Qingshu explained slowly with a playful look on his face, “When I held you and stepped on the Wooden Sword to fly, the airflow in the sky flowed through the lower surface of the Wooden Sword. The lower surface of the wooden sword is a flat surface, and on the upper surface of the wooden sword were me and you. Just then I deliberately controlled our body and the sword’s body to maintain a curved angle, so that the speed of the airflow passing through our body would be much greater than that of under the Wooden Sword. The logic behind the matter can be explained according to aerodynamics and Bernoulli’s Theorem, which talks about the flow of  fluid over a certain surface. It states that an increase in the speed of a fluid occurs simultaneously with a decrease in static pressure or a decrease in the fluid’s potential energy.

In aerodynamics, the four forces of flight are lift, weight, thrust and drag. These forces make an object move up and down, and faster or slower. The amount of each force compared to its opposing force determines how an object moves through the air. 

Lift is the push that lets something move up. It is the force that is the opposite of weight. Everything that flies must have lift. For the Wooden Sword to move upward, it must have more lift than weight.

The Wooden Sword is flatter on the bottom and we made it curved on top. That shape makes air flow over the top faster than under the bottom. As a result, less air pressure is on top of the Wooden Sword. This lower pressure makes the Wooden Sword, and us, to speed up, and move up.” _{(G: Bernoulli’s theorem of fluid dynamics, named after Daniel Bernoulli.)}

It turned out that when Song Qingshu flew over the lake on the Blackwood Cliff, he realized that as long as the speed was sufficient, the stone could float on the water surface, and he had been thinking hard about how to use the power of the water to truly cross the river with one reed. _(G:Idiom)

Originally, his thoughts lingered in the boundary of martial arts, hoping that he could fully understand the power of water. As a result, the more he thought about it, the more his head started to hurt. Until one day, an idea flashed across his mind, and he thought of the principle of aircraft in his previous life. In his past life, his company had done a project on aircrafts. He came across some knowledge behind the principles while he was researching related materials. So, he thought of using aerodynamics to solve the problem of Sword Flight.

“Aerodynamics? Bernoulli’s Theorem?” Dongfang Bubai frowned and asked in confusion, “Which martial arts secret book are these, why have I never heard of them?”

“Eh?” Song Qingshu was stumped, so he had to say, “Thay are the secret books of the Physics Sect in the extreme west, and naturally no one from the Central Plains has heard of them.”

“Physics Sect?” Dongfang Bubai fell into deep thought, then suddenly raised her head and asked, “According to what you said, flight is related to speed, right?”

“It’s a pity that you didn’t get to study physics…” Song Qingshu gave her a surprised look and nodded, “Yes, you can simply think that the greater the speed, the greater the lift the air will give you.”

“Oh!” Dongfang Bubai’s eyes were full of excitement, and she looked up at the sky, “If that is so, then as long as my speed is high enough, the lift the air will give me will be far greater than my own weight, so I can keep going up? Like the legendary ascending to heaven and becoming immortal?”

“You’re thinking too much.” As a modern person who knew that beyond the sky was just a lonely universe, Song Qingshu didn’t quite understand why Dongfang Bubai was so interested in things like ascending and going beyond the sky. 

“When the speed of flight exceeds the speed of sound, the air will become viscous, and you must consider the Reynolds number as well, which is not as simple as what I just said. Of course, if your speed can reach the speed of light, it would not be impossible to break free and ascend to heaven, but during the flight you will be burnt to ashes by the friction of the air.”

Dongfang Bubai became annoyed at his use of unfamiliar terms, and angrily asked, “Then tell me directly, is it impossible to ascend?”

“It’s possible.” Song Qingshu made a regretful expression, “Uh, I think you might want to care about your soaked clothes rather than these abstract things.”

---

Goblin: The $1 monthly membership is now available on Patreon. So, if you want to support me, you can choose to become a $1 Patron, which won’t hurt your pocket!

Patrons please visit the patreon page for your advanced chapter.

Want to read more? You can sponsor a chapter at BuyMeACoffee or become a patron at Patreon to enjoy advanced chapters!

Do you enjoy reading this novel? Show your support! Buy me some Coffee! And, please rate the novel at NU and leave a review if you have the time.

Thank you all for reading at Goblinslate!