"The Second Law of Mechanics: When an object is subjected to a resultant external force, it accelerates ......"

"In this physical model demonstration, for example, when the Earth is hit by Halley's Comet, the Earth will change its motion and produce acceleration. Pen, fun, pavilion www. biquge。 info”

Su Mufeng's voice spread in the void and empty space, and the ominous meaning revealed in his words made the faces of tens of thousands of students under the grass white.

! What kind of grudge do you have with the Lord of the Earth!

Especially when they connect the earth with the continent of Middle-earth, the horror and fear multiplies exponentially.

However, even with your eyes closed, the holographic projection of space is still clearly visible in front of you.

Everyone's tears were really close to falling.

After a century-long wait, Halley's Comet, a thousand kilometers in diameter, has finally approached Earth's gravitational sphere.

No, not close, I should say that I crashed into it!

Sixty-five million years ago, the age of dinosaurs could have ended when an asteroid with a diameter of 10 kilometers collided, altering the entire Earth's ecosystem.

After a hundredfold increase in diameter, what can this Halley's comet bring to Earth?

The answer is simple.

Earth, out of its established orbit.

――Straight in the direction of the sun!

"The direction of acceleration is the same as that of the resultant external force."

"In this physical model demonstration, Halley's Comet is in a straight line with the Earth and the Sun, so the direction of the Earth's acceleration is facing the Sun."

Su Mufeng's calm lecture continued.

This may be the most terrifying PPT lesson plan in human history?

After the violent impact of Halley's Comet, the Earth's rotation and revolution stopped at the same time, and the planet's orbit increased several times.

Coupled with Su Mufeng's deliberate projection acceleration, almost in an instant, the earth approached the sun.

It's like playing billiards, with a hole-in-one.

"The magnitude of acceleration is directly proportional to the magnitude of the resultant external force and inversely proportional to the inertial mass of the object."

"As shown in the diagram, Halley's Comet is experiencing a huge conjunctive force exerted on Earth, causing it to accelerate."

"At the same time, the inertial mass of the earth itself has reduced some of the acceleration."

In the next moment, the earth disappeared into the flames of the sun.

At the same time, the seven planets of the solar system also rioted with the disappearance of the earth!

However, Su Mufeng waved his hand, and they quieted down and obediently circled along the strange track.

Su Mufeng looked around and said with a smile: "The above is the second law of mechanics. ”

In the audience, more than 10,000 people shivered in unison.

"Well, do you understand?"

No one answered.

"Hey...... Well, let's experiment again! ”

The world was silent, and then, the ghost cried wolf howl, "Understood, ahh!!h ”

Teacher Su nodded with satisfaction and said with relief: "What a group of perceptive children. ”

The students burst into tears.

It is estimated that until they enter the coffin, they will not forget these laws of mechanics today.

Su Mufeng clapped his hands and said with a smile: "Now, let's start the demonstration of the third law of mechanics, and ask the students to observe carefully." ”

Everyone was numb and expressionless at this time.

Feel free to demonstrate!

Anyway, it's the solar system that will be destroyed, and God knows where in the universe?

It has nothing to do with us!

Hum!

Just as the students were comforting themselves, something new slowly emerged in space.

In the original position of the earth, two new ...... appeared. Earth?

It's like twins, except that the distribution of clouds, continents, and oceans is somewhat different.

In everyone's hearts, an ominous premonition gradually swelled up.

"Of these two planets, the first is the Earth, which has just been burned into a glass ball by the sun and has now been restored."

"The second one......"

With a malicious smile, Su Mufeng glanced at the confused students.

"This is our hometown, the Middle-earth continent."

"How? Doesn't it look kind? ”

Of course, this is a fool, Su Mufeng has never seen what the planet where the Central Continent is located looks like.

Besides, even if he has seen it, Chu Yan has never seen it! How is the database organized? How is the physical model organized?

So, just take a copy of the earth and make up the numbers.

Anyway, in the countries of Central Continent, except for Kong Sheng, no one has ever been to outer space.

On the side, after hearing Su Mufeng's answer, tens of thousands of people looked stunned.

Cordial?

Yes, yes......

If you don't burn it into a glass ball!

Just now, I was optimistically saying that "it wasn't my house that was smashed anyway", and now retribution is coming.

It was a real surprise.

The students burst into tears.

Su Mufeng smiled and said: "The third law of mechanics is actually very simple. ”

"There is a fixed law of action and reaction between two objects-"

"For example......

Before Su Mufeng's words fell, everyone understood what the hell this experiment was going to do!

Sure enough, in an instant, two parallel planets, driven by a mysterious force, rushed forward at the same time!

Similar planetary gravitational circles overlapped, and the atmosphere that bore the brunt of the attack instantly exploded, and then, the earth's crust hit straight ahead!

If you are on one of these planets, you can see the destruction of the "earth" falling from the sky and overturning everything!

“…… The law is that on the same straight line, the magnitude is equal and the direction is opposite. ”

"Taking the impact of the Earth and the Central Continent as an example, the physical effect is already very intuitive, and everyone must be able to see it at a glance."

Eventually, the remains of the two planets floated in the void, barely discernible in shape, like a mass of shaqima. It's just that they are tightly bound in place by an unknown source of gravity - not to smash the students thousands of kilometers away.

"Above, the third law of mechanics has been explained."

Su Mufeng waved his hand and said with a smile: "I hope that the students will review carefully after class!" ”

"Know...... Road...... ......"

Tens of thousands of people looked like ashes, and even their eyes were a little dull, looking like they had been played.

Seeing the mother planet being knocked into Shaqima with their own eyes, this psychological pressure, they can still speak, which is already a very durable performance.

The physical model demonstration was over, and Su Mufeng put away his smile and looked serious.

"Now, repeat the three laws of mechanics again."

"The first law, any object remains at rest or moves in a straight line at a uniform speed......"

"The second law, an object ...... when it is subjected to a resultant external force"

"The Third Law, the Force of Action and Reaction between Two Objects ......"

"Above—"

"It is the foundation of classical mechanics."

"Thus began classical mechanics to become a systematic natural science."

Almost at the moment when Su Mufeng's final judgment came out, between the voids, the bell rang!

The sound of thunder spread throughout the vast universe, and then left the Universal Fantasy Realm and spread to the entire Jixia Academy Palace, and even to the entire Middle-earth Continent!