What Is "movement" In Physics?

[isaac]

In physics, there are terms: mass, speed, acceleration, moment, force, work, energy, but nowhere has the term "movement". So I ask anyone who knows some physical law or equation in which a member of the equation is called a "movement" to let me know. Without that, I don't understand what "physics professors" think when they claim Sir Isaac Newton gave them "Laws of Movement"! So what is it?

 

I was taught at school that Sir Isaac Newton gave us the "Law of Force" and the three principles (laws) on the operation of that Force. The most important principle we first learned was the "action and reaction" principle, which we called the 3rd Newton Law. Afterwards, we learned the "principle of equilibrium" (when the sum of the forces on a body equals zero), and we called this principle the 1st Newton's Law. In the end, we also learned the "principle of change" (when a force changes the speed of a mass), and we called this principle the 2nd Newton's Law. So all three principles are part of the Law of Force (F = ma)!

 

So how did we mathematically explain these laws of Force?

3rd Newton's Law states (Each action of a Force is divided into two symmetric forces: Force of action and Force of reaction): F_a = F_r,

1st Newton's law states (In equilibrium the sum of all Forces of action and Forces of reaction equals zero): F_a + F_r = 0,

2nd Newton's law states (Always, at the same time, doing the work, both the Force of Action and the Force of Reaction)) that 

the total acting force is F_w = F_a + F_r , so according to the 3rd law: F_w = 2F_a = 2F_r, that is, F_w = (ma)_a + (ma)_r = 2(ma)_w.

 

"Force of Reaction", we have also popularly called "sluggishness" or "inertia"!

 

At school I also learned that the integral of a force along the path and time is equal to the work of that force, that is, the energy consumed! Well, according to Newton's 2nd Law, the total energy consumed was 2E_w = E_a + E_r, which we called: "The Law of Conservation of Energy", and this law was explained to us by the teacher on the example and principle of "cannon", "rocket" and "satellite":

(2E_w)_gunpowder = (E_a)_cannonball + (E_r)_{jerk of cannon},

(2E_w)_{rocket fuel} = (E_a)_{fuel particle acceleration} + (E_r)_{rocket acceleration},

(2Ew)_{rocket fuel} = (E_a)_{lifting the satellite to orbit} + (E_r)_{accelerating the satellite to orbital speed},

Well that's as clear as day!

 

But why did the teacher tell us that the "Weight" of the body equals the force by which "Earth attracts the body"? Well, I didn't understand that! Well, not only is the body attracted to the Earth, but also "The body is attracting the Earth"! Well, the same thing tells us and Newton's 2nd Law: F_w = 2ma as well as the Law of Gravity: F_G = 2mg! Each spring has two ends! So it would be correct to say: "Weight" is 1/2 of the force with which attract - "Earth and body"! In the opposite case, there is as much "dark mass and energy" in the Universe as you want!

 

Perhaps the term and the phenomenon of "movement" should apply to our "professors of physics" and their "textbooks"?

 

[OceanBreeze]

While “movement” is close, the correct term in physics is motion, and quite a lot can be said about it!

 

In physics, motion is the change in the position of an object over time. Motion is mathematically described in terms of displacement, distance, velocity, acceleration, speed, and time. The motion of a body is observed by attaching a frame of reference to an observer and measuring the change in position of the body relative to that frame.

 

[exchemist]

 

In physics, there are terms: mass, speed, acceleration, moment, force, work, energy, but nowhere has the term "movement". So I ask anyone who knows some physical law or equation in which a member of the equation is called a "movement" to let me know. Without that, I don't understand what "physics professors" think when they claim Sir Isaac Newton gave them "Laws of Movement"! So what is it?

 

I was taught at school that Sir Isaac Newton gave us the "Law of Force" and the three principles (laws) on the operation of that Force. The most important principle we first learned was the "action and reaction" principle, which we called the 3rd Newton Law. Afterwards, we learned the "principle of equilibrium" (when the sum of the forces on a body equals zero), and we called this principle the 1st Newton's Law. In the end, we also learned the "principle of change" (when a force changes the speed of a mass), and we called this principle the 2nd Newton's Law. So all three principles are part of the Law of Force (F = ma)!

 

So how did we mathematically explain these laws of Force?

3rd Newton's Law states (Each action of a Force is divided into two symmetric forces: Force of action and Force of reaction): F_a = F_r,

1st Newton's law states (In equilibrium the sum of all Forces of action and Forces of reaction equals zero): F_a + F_r = 0,

2nd Newton's law states (Always, at the same time, doing the work, both the Force of Action and the Force of Reaction)) that 

the total acting force is F_w = F_a + F_r , so according to the 3rd law: F_w = 2F_a = 2F_r, that is, F_w = (ma)_a + (ma)_r = 2(ma)_w.

 

"Force of Reaction", we have also popularly called "sluggishness" or "inertia"!

 

At school I also learned that the integral of a force along the path and time is equal to the work of that force, that is, the energy consumed! Well, according to Newton's 2nd Law, the total energy consumed was 2E_w = E_a + E_r, which we called: "The Law of Conservation of Energy", and this law was explained to us by the teacher on the example and principle of "cannon", "rocket" and "satellite":

(2E_w)_gunpowder = (E_a)_cannonball + (E_r)_{jerk of cannon},

(2E_w)_{rocket fuel} = (E_a)_{fuel particle acceleration} + (E_r)_{rocket acceleration},

(2Ew)_{rocket fuel} = (E_a)_{lifting the satellite to orbit} + (E_r)_{accelerating the satellite to orbital speed},

Well that's as clear as day!

 

But why did the teacher tell us that the "Weight" of the body equals the force by which "Earth attracts the body"? Well, I didn't understand that! Well, not only is the body attracted to the Earth, but also "The body is attracting the Earth"! Well, the same thing tells us and Newton's 2nd Law: F_w = 2ma as well as the Law of Gravity: F_G = 2mg! Each spring has two ends! So it would be correct to say: "Weight" is 1/2 of the force with which attract - "Earth and body"! In the opposite case, there is as much "dark mass and energy" in the Universe as you want!

 

Perhaps the term and the phenomenon of "movement" should apply to our "professors of physics" and their "textbooks"?

 

You do not understand Newton's laws very well, do you? 

 

Consider a 1k bag of sugar sitting on your kitchen table. Its weight is ~10N, as you can verify with a spring balance.

 

But is it moving with respect to the kitchen? No.

 

So what do Newton's laws allow us to conclude? That no net force is acting on the bag of sugar.

 

So there is un upthrust acting on it from the table, exactly equal to its weight, i.e. ~10N. 

 

You can't add these and get 20N. When you add them you get zero N. This is because they act in opposite directions and cancel. (In other words, forces are vectors: they have direction as well as magnitude.)

[isaac]

Dear Exchemist, do you read what you write at all?

Well, you just explained to all the housewives on the Planet that if they put 1 kg of sugar on the kitchen table, that in an instant, the "net force on that sugar will be 0" so their sugar will be in weightless state immediately !!!

 

You have to "mandatory" re-read what I wrote! Also send it to your "professor of physics" (don't send him what you wrote!)!

 

Well, since you like to weigh sugar, I'll explain to you how your balance works (and you explain it to your "physics professor" later). Your sugar has a "weight" of 1 kg as well as The International Prototype of the Kilogram located in Paris. Now if you take 1 kg of sugar and put it on one weighting plate of scale, you must also put a mass of 1 kg on the other plate of scale. How much kg do you have on the scale then? What is the total "weight" of "sugar and weight"? 2 kg right? Not 0 as you claim! Why do we, on a balance scale, "have to have" 2 kg? Because the Earth "pulls" the sugar by a force of 1 kg, but at the same time the sugar "pulls" the Earth by a force of 1 kg, so the total attractive force (weight) is 2 kg. The same is what Newton's 2nd law tells us: F_w = F_a + F_r = 2F_a = 2mg!

 

But since you prefer to weigh sugar, with spring balance, I'll also explain to you how this device works. If you hang 1 kg of sugar on your spring balance, with how much force, do you have to keep your balance in balance? And the same with another 1 kg! So what is the tension force in your spring by which you are weighting? 2 kg right? Not 0 as you claim! F_w = F_a + F_r = 2F_a = 2mg!

 

You and your professor have forgotten that each spring has two ends (3rd Newton law! F_a = F_r, F_w = F_a + F_r)! The force in the spring is the sum of the forces from both ends of the spring! Therefore, the force in the spring is not a vector but a symmetric tensor with two opposite directions! The same is true for gravity F_G = 2mg!

 

Your professor must have "taught" you that "there is", in addition to Newton's law of force, and Hook's law of force: F = k x ! Interesting "some physics" with two laws of force!? Even the "little child" sees that Hook's law is not a law of force, but of work (energy) that must be done to deform a spring: W = F x = k x [Nm], F = k [N]. So what kind of "Physics" is it, based on the wrong law of force and in which, instead of Newton's Law of Force, the "Laws of movement" rule? Wrong!

 

Our "physics professors" write thick books about gravity, entropy, the ideal fluid, the laws of movement, dark mass and energy, astrophysics and the theory of everything. They would "correct and deny" Newton, but they don't know how to add 1 + 1! Shame!

[exchemist]

 

Dear Exchemist, do you read what you write at all?

Well, you just explained to all the housewives on the Planet that if they put 1 kg of sugar on the kitchen table, that in an instant, the "net force on that sugar will be 0" so their sugar will be in weightless state immediately !!!

 

You have to "mandatory" re-read what I wrote! Also send it to your "professor of physics" (don't send him what you wrote!)!

 

Well, since you like to weigh sugar, I'll explain to you how your balance works (and you explain it to your "physics professor" later). Your sugar has a "weight" of 1 kg as well as The International Prototype of the Kilogram located in Paris. Now if you take 1 kg of sugar and put it on one weighting plate of scale, you must also put a mass of 1 kg on the other plate of scale. How much kg do you have on the scale then? What is the total "weight" of "sugar and weight"? 2 kg right? Not 0 as you claim! Why do we, on a balance scale, "have to have" 2 kg? Because the Earth "pulls" the sugar by a force of 1 kg, but at the same time the sugar "pulls" the Earth by a force of 1 kg, so the total attractive force (weight) is 2 kg. The same is what Newton's 2nd law tells us: F_w = F_a + F_r = 2F_a = 2mg!

 

But since you prefer to weigh sugar, with spring balance, I'll also explain to you how this device works. If you hang 1 kg of sugar on your spring balance, with how much force, do you have to keep your balance in balance? And the same with another 1 kg! So what is the tension force in your spring by which you are weighting? 2 kg right? Not 0 as you claim! F_w = F_a + F_r = 2F_a = 2mg!

 

You and your professor have forgotten that each spring has two ends (3rd Newton law! F_a = F_r, F_w = F_a + F_r)! The force in the spring is the sum of the forces from both ends of the spring! Therefore, the force in the spring is not a vector but a symmetric tensor with two opposite directions! The same is true for gravity F_G = 2mg!

 

Your professor must have "taught" you that "there is", in addition to Newton's law of force, and Hook's law of force: F = k x ! Interesting "some physics" with two laws of force!? Even the "little child" sees that Hook's law is not a law of force, but of work (energy) that must be done to deform a spring: W = F x = k x [Nm], F = k [N]. So what kind of "Physics" is it, based on the wrong law of force and in which, instead of Newton's Law of Force, the "Laws of movement" rule? Wrong!

 

Our "physics professors" write thick books about gravity, entropy, the ideal fluid, the laws of movement, dark mass and energy, astrophysics and the theory of everything. They would "correct and deny" Newton, but they don't know how to add 1 + 1! Shame!

 

Ah, just another madman, I see. Have a nice day. 

 

[click]

[OceanBreeze]

I'm guessing isaac here needs to sit on his bags of sugar to prevent them from being moved around by that net force that is always acting on them.

[sluggo]

Gravity is always 'on'. F=ma=mg equals 'weight'.

The gravitational field is constantly accelerating the mass m toward the earth center.

The table gets in the way of the bag of sugar, or resists its motion.

This explains why you can insert a scale between you and the ground to know your weight!