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I am not sure what is your question,
Just to make sure that you actually understand what conservation of momentum means (because it's far from clear that you do), take a look at this quote from "the Physics Classroom" website: https://www.physicsclassroom.com/class/momentum/Lesson-2/Momentum-Conservation-PrincipleQuoteOne of the most powerful laws in physics is the law of momentum conservation. The law of momentum conservation can be stated as follows.For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.The above statement tells us that the total momentum of a collection of objects (a system) is conserved - that is, the total amount of momentum is a constant or unchanging value.I bolded the important bit. Based on this, do you understand that conservation of momentum means that the total momentum of a closed system cannot change?
One of the most powerful laws in physics is the law of momentum conservation. The law of momentum conservation can be stated as follows.For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.The above statement tells us that the total momentum of a collection of objects (a system) is conserved - that is, the total amount of momentum is a constant or unchanging value.
Quote from: Jaaanosik on 22/04/2020 05:30:51I am not sure what is your question,It's here. The sentence that is underlined:Quote from: Kryptid on 22/04/2020 00:35:06Just to make sure that you actually understand what conservation of momentum means (because it's far from clear that you do), take a look at this quote from "the Physics Classroom" website: https://www.physicsclassroom.com/class/momentum/Lesson-2/Momentum-Conservation-PrincipleQuoteOne of the most powerful laws in physics is the law of momentum conservation. The law of momentum conservation can be stated as follows.For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.The above statement tells us that the total momentum of a collection of objects (a system) is conserved - that is, the total amount of momentum is a constant or unchanging value.I bolded the important bit. Based on this, do you understand that conservation of momentum means that the total momentum of a closed system cannot change?
Yes
The cat burning potential energy is losing atoms, mass is getting out of the system.The rotating cat is not a closed system.Jano
What is causing the wobble of the CD players when they are ON and when they receive gentle external impulse?Where is the action and counter-reaction coming from?
The black ball is a closed system.The dark blue wheel is a closed system.
The conclusion is that the internal subsystems can change their values, conversion from one momentum to another.Even a conversion from linear to angular.
Quote from: Jaaanosik on 22/04/2020 05:20:57The black ball is a closed system.The dark blue wheel is a closed system.The very moment that those two objects interact with each other, they cease to be closed systems. A closed system is one that does not interact with other systems....
Where do you get your definition that "A closed system is one that does not interact with other systems"?
...This is called gyroscopic precession. This video explains the physics behind it: //www.youtube.com/watch?v=n5bKzBZ7XuMNothing about it violates conservation of angular momentum....
Quote from: Jaaanosik on 22/04/2020 06:08:22Where do you get your definition that "A closed system is one that does not interact with other systems"?I have to admit, I had not encountered the definition of closed system that you posted before. An isolated system is more what I was thinking.In any case, the spaceship is not only a closed system, but also an isolated system (it doesn't utilize any external mechanisms. It tries to move using only its internal mechanisms). That being said, do you agree that its momentum must remain unchanged since it is an isolated system?
If this was a simple gyro precession then the CD players body would not wobble.
We need to know where you got your definition.As mentioned, the only system is the whole Universe based on your definition,Jano
Quote from: Jaaanosik on 22/04/2020 06:16:13If this was a simple gyro precession then the CD players body would not wobble.Gyroscopic precession does cause a wobble. It's what causes a spinning top to wobble.So how about answering my question?Quote from: Jaaanosik on 22/04/2020 06:18:47We need to know where you got your definition.As mentioned, the only system is the whole Universe based on your definition,JanoThis is one such example: https://www.dictionary.com/browse/closed-system
Really???A dictionary definition???
What is your question?
In any case, the spaceship is not only a closed system, but also an isolated system (it doesn't utilize any external mechanisms. It tries to move using only its internal mechanisms). That being said, do you agree that its momentum must remain unchanged since it is an isolated system?
How is the gyro precession causing a wobble?
Is it in the youtube videos? Where the gravity is involved?Do you have a single wheel precession in micro-gravity?
Quote from: Jaaanosik on 22/04/2020 06:31:20Really???A dictionary definition???And what is your problem with dictionaries?Quote from: Jaaanosik on 22/04/2020 06:31:20What is your question?This:Quote from: Kryptid on 22/04/2020 06:15:48In any case, the spaceship is not only a closed system, but also an isolated system (it doesn't utilize any external mechanisms. It tries to move using only its internal mechanisms). That being said, do you agree that its momentum must remain unchanged since it is an isolated system?Remember, no momentum is entering or leaving the ship.
Quote from: Jaaanosik on 22/04/2020 06:37:40How is the gyro precession causing a wobble?It's explained by Wikipedia here: https://en.wikipedia.org/wiki/Precession#Classical_(Newtonian)Quote from: Jaaanosik on 22/04/2020 06:37:40Is it in the youtube videos? Where the gravity is involved?Do you have a single wheel precession in micro-gravity?Gravity is not involved.Now answer my question.
There is no wobble from a single gyro in micro-gravity, check the video.
Please, what is your question?
Quote from: Jaaanosik on 22/04/2020 06:45:06There is no wobble from a single gyro in micro-gravity, check the video.I can see it wobble. The wobble is just very small.Quote from: Jaaanosik on 22/04/2020 06:45:06Please, what is your question?You already asked me this before. My question is in reply #191.
Dictionary is not a textbook
There is no answer till we settle the closed system definition.
Quote from: Jaaanosik on 22/04/2020 06:53:53Dictionary is not a textbookYour point being what?Quote from: Jaaanosik on 22/04/2020 06:45:06There is no answer till we settle the closed system definition.The spaceship is an isolated system. That is clearly defined. No matter or energy is entering or leaving the system. No momentum is entering or leaving the system either.So if a system does not have momentum entering or leaving it, you understand that the momentum must remain unchanged, yes?
Do you understand what it means?
The cat is isolated system, correct?
How the cat could start the rotation without an external impulse?