I Is it possible to "violate" momentum at the expense of more energy?

  • I
  • Thread starter Thread starter gggnano
  • Start date Start date
  • Tags Tags
    Energy Momentum
AI Thread Summary
The discussion centers on the feasibility of creating unidirectional movement in a closed cylinder by applying force to a gas or solid ball, drawing parallels to the EmDrive concept. It questions whether continuous energy input can overcome momentum, suggesting that while theoretically possible, it may require increasingly more energy, making it impractical. The conversation highlights the limitations of momentum conservation, stating that any force applied will result in an equal and opposite reaction, maintaining the center of mass. Ultimately, the consensus leans toward the impossibility of achieving perpetual motion or effective propulsion with this method. The thread concludes with a note that discussions on EmDrive are prohibited in the forum.
gggnano
Messages
43
Reaction score
3
TL;DR Summary
Produce thrust in a closed chamber when the opposite momentum is compensated with more energy?
This is in fact a shamelessly simple question to a point the reason it puzzles me is because it's too simple:

So basically you have a closed empty/hollow cylinder filled with either gas or even an ordinary solid ball...and then on the left side of the cylinder you put a force on the "fuel" (gas/ball...) so that it moves to the other side and hits it producing movement. Now, since the ball will come back once it hits the right side then can you produce movement ONLY in one direction for as long as you increase the energy from the left side that pushes the ball?

In fact this idea is very similar to the "emdrive" concept:

http://nerdist.com/wp-content/uploads/2014/08/EmDrive.jpg

Yet I am not sure if the "emdrive" design realizes they will need more and more energy to battle the bouncing wave so perpetuum mobile is impossible?

And if this is possible at tall then you may say it's useless since you need more and more energy to combat momentum yet notice how if you have strong amount of heat but limited amount of fuel this is very useful. For example: you can use million degrees hot nuclear reaction in a rocket but you cannot find fuel in the cosmos to recharge the rocket...well it's not easy...thank you!
 
Physics news on Phys.org
You can do anything you want if you have a sufficient supply of ""s.

Other than that, from what I can parse, you might consider that "putting a force" on the inside component to make it go to the right will cause the outside component to go to the left. No matter what you do, the centre-of-mass stays in the same place.

(If I remember, correctly) the Em drive is supposed to use some abstract group property of EMR ; the illustration you've linked to simply shows a fancier version of what you've got... which doesn't work.
 
Last edited:
  • Like
Likes Ibix
Thread 'Gauss' law seems to imply instantaneous electric field'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Hello! Let's say I have a cavity resonant at 10 GHz with a Q factor of 1000. Given the Lorentzian shape of the cavity, I can also drive the cavity at, say 100 MHz. Of course the response will be very very weak, but non-zero given that the Loretzian shape never really reaches zero. I am trying to understand how are the magnetic and electric field distributions of the field at 100 MHz relative to the ones at 10 GHz? In particular, if inside the cavity I have some structure, such as 2 plates...
Back
Top