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Quote from: Jaaanosik on 09/04/2020 01:31:51Is horizontal component slowing down the ship?Yes. All of the kinetic energy possessed by the ship and balls is stored in the springs at the end of the interaction. Keep in mind that the springs are technically being pressed from both the bottom (due to the ship's velocity) and the top (due to the ball's velocity). An equal amount of energy is being absorbed from both the ship and the balls in the process because both the balls and the ship have the same mass.
Is horizontal component slowing down the ship?
No, the horizontal component is not going to slow down the spaceship.No work is done to slow down the spaceship.How do we know?Because work is a dot product of F and s.The force is 90 degrees to the trajectory of the spaceship, no work is done.F*s = 0 (as a dot product)Jano
Now to continue along the line.When the ball pushes the horizontal spring shaft then it is doing a work.
The trajectory s is horizontal and the inertia of the ball is pushing the shaft - the ball is doing work F*s.The ball is losing its kinetic energy, transferred to the horizontal spring potential energy,... but it is NOT slowing down the ship!
Quote from: Jaaanosik on 09/04/2020 01:44:35No, the horizontal component is not going to slow down the spaceship.No work is done to slow down the spaceship.How do we know?Because work is a dot product of F and s.The force is 90 degrees to the trajectory of the spaceship, no work is done.F*s = 0 (as a dot product)JanoIf no work is being done to slow down the ship, then no work is being done to slow down the balls either. Remember, just as much energy entering the springs is coming from the ship as is coming from the balls. The fact that kinetic energy is being removed from the balls and the ship to compress the springs means that both must be slowed down.Quote from: Jaaanosik on 09/04/2020 02:13:09Now to continue along the line.When the ball pushes the horizontal spring shaft then it is doing a work.And when the ship is pushing the spring against the ball, it is doing work as well.QuoteThe trajectory s is horizontal and the inertia of the ball is pushing the shaft - the ball is doing work F*s.The ball is losing its kinetic energy, transferred to the horizontal spring potential energy,... but it is NOT slowing down the ship!If the balls are losing kinetic energy, then the ship is too. Remember, the situation is perfectly symmetrical. From the reference frame of the balls, the balls are sitting still and the springs are moving towards them. From the balls' point of view, the kinetic energy of the ship-spring system is what is compressing the springs because the balls have no kinetic energy in their own reference frame. From the reference frame of the barycenter, energy from both the balls and the ship are being used to compress the springs.
The balls velocity component down is getting smaller because of this rotation in the barycenter frame.
The spaceship velocity component up is not getting smaller because the spaceship does not rotate in the barycenter frame.
The work done on the spring did not change the spaceship velocity/momentum in the barycenter frame.
I hope this helps,
Kryptid,The spaceship moves upwards/forward.Are you saying that the horizontal motion will slow down the spaceship?Are you saying that winding-up the springs on the absorbers will slow down the spaceship?Jano
How big momentum goes to the bottom absorber (on the right now)?
Do you have a new theory about momentum?
Quote from: Jaaanosik on 09/04/2020 23:16:35How big momentum goes to the bottom absorber (on the right now)?All of the ball's forward momentum goes into it.Quote from: Jaaanosik on 09/04/2020 23:16:35Do you have a new theory about momentum?No. I have no need for it. The existing one is good enough.
Kryptid,The bold part, you are not serious, are you?Jano
Quote from: Jaaanosik on 10/04/2020 01:07:42Kryptid,The bold part, you are not serious, are you?JanoOn second thought, perhaps not. I imagine some of the forward momentum could be transmitted to the ship floor through the bottom spring (not by compressing the bottom spring, mind you, but by applying a sideways force through the rod connecting it to the floor). The exact ratio of how much of the forward momentum goes into compressing the right spring and how much gets transmitted through the rod holding the bottom spring, I do not know. It ultimately doesn't matter though, as the total must necessarily be equal and opposite to the amount of the ship's momentum (due to Newton's third law) it cancels out. If the ball comes to a complete stop, then the ship has to as well. That's Newton's third law.
We have a forward net momentum.
We could spend all day talking about various designs, but the fact of the matter is that the laws of physics will not allow them to work. We know before we begin any kind of analysis that the total momentum of the system must be identical at all stages of the machine's working. If you discover at the end of your analysis that the total momentum has changed, then you must have made an error in your analysis somewhere. This is demanded by conservation of momentum. Conservation of momentum, in turn, is demanded by Noether's theorem: https://en.wikipedia.org/wiki/Noether%27s_theoremTake note how Noether's theorem is a theorem and not a theory. A theory is supported by scientific evidence, whereas a theorem is supported by mathematical proof: https://en.wikipedia.org/wiki/Theorem
Quote from: Jaaanosik on 10/04/2020 02:34:08We have a forward net momentum.I think you missed this:Quote from: Kryptid on 09/04/2020 20:46:59We could spend all day talking about various designs, but the fact of the matter is that the laws of physics will not allow them to work. We know before we begin any kind of analysis that the total momentum of the system must be identical at all stages of the machine's working. If you discover at the end of your analysis that the total momentum has changed, then you must have made an error in your analysis somewhere. This is demanded by conservation of momentum. Conservation of momentum, in turn, is demanded by Noether's theorem: https://en.wikipedia.org/wiki/Noether%27s_theoremTake note how Noether's theorem is a theorem and not a theory. A theory is supported by scientific evidence, whereas a theorem is supported by mathematical proof: https://en.wikipedia.org/wiki/Theorem
Where did I break the conservation of energy or conservation of momentum?
What is wrong with changing the linear momentum to angular momentum?
Quote from: Jaaanosik on 10/04/2020 06:40:44Where did I break the conservation of energy or conservation of momentum?When the spacecraft starts off, it is stationary. The total momentum of the system is zero. So if the total momentum ever changes from zero, then conservation of momentum has been violated. You claim that your system creates net momentum and therefore you claim that your system can violate conservation of momentum.Quote from: Jaaanosik on 10/04/2020 06:40:44What is wrong with changing the linear momentum to angular momentum?Linear momentum and angular momentum are both their own, conserved phenomena. They are not interchangeable. If the linear momentum and angular momentum both start off at zero, then both must remain at zero.
Linear momentum and angular momentum are both their own, conserved phenomena. They are not interchangeable. If the linear momentum and angular momentum both start off at zero, then both must remain at zero.
we can transform kinetic energy to rotational energy but we cannot transform linear momentum to angular momentum?
So the increase of the internal kinetic energy cannot be transformed to external kinetic energy?
Are you sure the linear momentum cannot be converted to angular momentum?
Where is the conservation of energy broken here?
Quote from: Jaaanosik on 10/04/2020 17:26:18we can transform kinetic energy to rotational energy but we cannot transform linear momentum to angular momentum?No, you can't: https://van.physics.illinois.edu/qa/listing.php?id=24173&t=is-linear-momentum-converted-to-angular-momentumQuote from: Jaaanosik on 10/04/2020 17:26:18So the increase of the internal kinetic energy cannot be transformed to external kinetic energy?It can't produce net momentum, no.Quote from: Jaaanosik on 10/04/2020 17:26:18Are you sure the linear momentum cannot be converted to angular momentum?Yes. See the link above.Quote from: Jaaanosik on 10/04/2020 17:26:18Where is the conservation of energy broken here?It isn't. Conservation of momentum is what is broken.