Among the crowd, Qin Feng talked eloquently: "Do you think that there is no such friction force for stationary objects?"
"Isn't it?" everyone asked in unison.
Qin Feng waved his finger: "Wrong, big mistake!
The stillness you see is just the result of friction and other forces canceling each other out!
In fact, this power is always there! "
"Still with the example just now, it is difficult to push a wine glass on rough ground because of the friction coefficient, which causes it to receive a strong friction force, which offsets your pushing force!
However, as long as the pushing force you exert is greater than this friction force, the cup can still be pushed!
I say this, can you understand? "
Everyone was enlightened and suddenly enlightened: "So this is what happened."
Yuan Zhai naturally had more in mind than these people: "In other words, sometimes the shape of the wheel I choose cannot drive the heavy object forward. Is it because the friction is too great?
In this case, the wheels can still only choose round objects to reduce friction.
But this will cause the original problem to arise again. When the car is traveling on relatively soft plains or mountains, the wheels will easily sink into the mud under heavy pressure..."
If you want to build a mobile city, various terrain factors must be taken into consideration.
However, after some enlightenment, although the veteran understood the reason for the failure, he fell into an endless loop again.
After hearing this, everyone in Shen Gongfang lowered their heads in thought and fell into confusion.
"This problem is not impossible to solve." After a long time, Qin Feng slowly spoke.
Everyone suddenly looked up at him, and the elders also cast curious glances.
Qin Feng didn't say anything more, but did a comparative test.
He led everyone to a tree planted with flowers, which was full of soil.
He ordered people to find two stones of similar weight, one with a flat bottom and the other with a sharp bottom.
Two stones were placed on the soil at the same time. The flat stone was stable, while the sharp stone below slowly sank.
The elders and others thought thoughtfully, this phenomenon that used to be commonplace in the eyes of everyone has now become somewhat unusual.
They have never thought carefully about the reasons behind some things that should happen in life.
Qin Feng smiled and said: "Under the premise of the same weight, the smaller the force-bearing area, the greater the effect of the force.
Haven't you ever thought about it?
Why are the heads of all weapons mostly shaped like spikes instead of other shapes?
Why does one side of a knife have to be polished to be extremely sharp, but when cutting things, people don’t use the dull side?
Why can a needle and thread easily pierce clothing, but not the palm of my hand?
Why is the eighty-year-old lady...ahem. "
I almost let it slip again. I misled me when I approached science... Qin Feng looked a little embarrassed: "It all comes down to the effect of force. I call it pressure."
Everyone in Shen Gongfang was stunned for a moment, then lowered their heads to think, and then suddenly became enlightened, and there was a constant stream of admiration. Please download the app Aiyue app for the latest content
"That's it, that's it!"
"In the past, I only knew what happened, but I didn't know why. Today, I benefited greatly from listening to Mr. Qin's words!"
"I suddenly had a brilliant idea. If the blunt side of the knife was forged into a sharp shape, wouldn't the lethality be greatly increased?"
"Isn't it the sword you're talking about?"
"..."
Everyone was still immersed in the joy of learning new knowledge, when the elder suddenly shouted: "Quiet!"
He looked up at Qin Feng, frowned and said: "The wheel will sink into the mud because the weight it bears is too large, and the force-bearing area of the wheel is too small.
So there are only two ideas to solve this problem, either reduce the weight or increase the stress area of the wheel? "
Is the idea very clear... Qin Feng smiled and nodded.
The veteran then said in a deep voice: "But the friction you mentioned before is also affected by the contact area. If I increase the size of the wheel.
Will it cause too much friction and make the car unable to move forward? "
"Won't."
"Why?"
Qin Feng kept smiling and did not answer.
This involves the concepts of sliding friction and rolling friction, which are not easy to explain...
"A mature craftsman, after knowing the principles, should learn to think for himself." Qin Feng muttered and gave a universal answer.
Hearing this, everyone in Shen Gongfang narrowed their eyes slightly and nodded in approval.
The master led them in. They still understood the principle of personal cultivation.
Even Yang He, who was standing aside, pretended to smile and said, "That's right."
Lan Ningshuang was curious: "Did you understand what my uncle said?"
Of course I don't understand... Yang He chuckled softly: "After all, your warriors' understanding is still a little bit behind. Hundred Ghost Taoists and Wen Sheng Taoists are cultivating the same soul.
This understanding ability is naturally similar. "
Lan Ningshuang was speechless, Zhang Tiannan glanced sideways, his eyes full of doubts.
"How do you know this knowledge?" The elder asked the doubts in the hearts of everyone present.
Qin Feng glanced at everyone, smiled and said: "I once had a teacher who taught me a lot of knowledge.
These are one of them.
Of course, what I benefited most from was understanding a truth from my teacher.
Never be bound by ordinary rules, learn to break them. Only in this way can you discover a new world you have never seen before! "
Yes, the teacher's name is High School Physics, People's Education Press...
The elder naturally heard Qin Feng's words. He stood up, looked at the other party, and asked: "What other knowledge is there?"
There's drama!
Qin Feng raised his eyebrows and blurted out: "Of course there are many, many!
Why do things fall to the ground instead of flying into the sky?
Why are the swimming positions of fish in the water always slightly different from what we see?
On a rainy day, why do we see thunder first and then hear it?
What are the principles behind these common things?
Don't you want to know? "
"Think!" Everyone shouted immediately.
They seemed to see the door to a new world slowly opening.
"But I'm sorry, I can't tell you. After all, I promised the teacher at the beginning that this knowledge cannot be easily passed on to others.
Otherwise, the rules are broken.
What I just described about the mysteries of friction and pressure has actually gone a bit too far.
I can't make another mistake again and again. "While speaking, Qin Feng glanced at the elder, who frowned.
The rest of the Shen Gongfang group was scratching their heads in anxiety.
This is like a brothel, the pretty girl is lying on the bed, the man has taken off his clothes and is about to gallop, but the girl says that there is sunflower water.
You can only look at it, but you can't touch it...
Who can stand this?
Huo Yuan asked: "Brother Qin, can't you be accommodating? We are willing to spend money!"
Qin Feng showed displeasure: "How can knowledge be measured with yellow and white things?!"
"this......"
Just when everyone was at a loss what to do, the veteran who had been silent until now sighed: "Later, you can bring the materials for forging the sword.
Also, these new things you mentioned..."
"Junior, when the time comes, write it down and bring it with you!" Qin Feng said excitedly.
The people in Shen Gongfang were greatly surprised. The elder actually wanted to make an exception and forge the same weapon twice!
And they looked at Qin Feng, with strange expressions on their faces: "Master Qin, shouldn't this knowledge not be easily passed on to others?"
Qin Feng's face turned red and he coughed dryly: "Don't worry about these insignificant details..."
