Why is this apparent violation of the action and reaction law occurring?

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In summary, the conversation discusses an apparent violation of the action and reaction law, where EM waves are able to exert forces without a simultaneous reaction. However, it is explained that all forces in the universe have a delay between action and reaction. The possibility of using this principle to create a thruster is also mentioned. The conversation also touches on the concept of hidden momentum in the EM field and the idea that EM forces can occur without a closed circuit. Ultimately, the conversation is deemed as a crackpot idea and the thread is locked.
  • #1
Ulysees
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Here's an apparent violation of the action and reaction law:

[crackpot link deleted]

How can it be? Surely EM waves exert forces on objects all the time, nothing new to action without reaction (EM waves are not like sound waves where there is a medium and the medium experiences the reaction).

But then, all forces in the universe have a delay between action and reaction, because there is always a distance between the interacting charges or masses or whatever it is for the strong and weak nuclear force.
 
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  • #2
There is no convincing evidence that ion lifters don't just accelerate ions in the air. I'll wait for discussion with the other mentors, but I consider this a crackpot idea.
 
  • #3
Alright but wait a sec, I think this page was not intended to prove that his flying machine exhibits antigravity, just that EM forces can occur without a simultaneous reaction.

It happens all the time, EM waves arriving to a radio receiver exert forces to the electrons in the antenna. These electrons experience force without simultaneous reaction.
 
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  • #4
This paradox is resolved by assigning a "hidden momentum" to the EM field itself. This can be done in a consistent way such that momentum is always conserved (i.e., whatever momentum you put into the fields, you can get back out of them again).

Note that since the electrons experience forces, they must accelerate. And since they must accelerate, they must radiate. I think calculations of the photons thus radiated would show that they carry away momentum that balances whatever is gained by the CM of the electron-electron system. Thus, any thruster designed on this principle would work by means of shooting photons out the rear.
 
  • #5
Apparently the lower foil is not connected to anything! :rolleyes:

Only the upper wire is connected to high voltage.

How can there be continuous current, charge flow, if the circuit is not closed?
 
  • #6
Ulysees said:
Alright but wait a sec, I think this page was not intended to prove that his flying machine exhibits antigravity, just that EM forces can occur without a simultaneous reaction.
Whatever direction he wants to introduce it from, it doesn't matter. It's still a violation of conservation of energy.
It happens all the time, EM waves arriving to a radio receiver exert forces to the electrons in the antenna. These electrons experience force without simultaneous reaction.
Not true. EM radiation has to be emitted by something, so the reaction force is on the object emitting the radiation. This is the principle by which a solar sail works.

Thread locked, crackpot link deleted.
 

1. Why does it seem like the action and reaction law is being violated?

This is a common question when observing certain situations where the expected equal and opposite reaction does not seem to occur. It is important to understand that the action and reaction law, also known as Newton's third law of motion, applies to isolated systems and may not always be apparent in complex systems with multiple forces and interactions.

2. Can the action and reaction law be broken?

No, the action and reaction law is a fundamental principle in physics and cannot be broken. It has been extensively tested and proven to hold true in all observed cases of motion and force.

3. What are some examples of apparent violations of the action and reaction law?

One common example is the motion of a rocket. The rocket exerts a force downwards to produce an equal and opposite reaction force upwards, but it appears that the rocket is moving upwards without any visible reaction force. This is because the rocket is also experiencing an equal and opposite force from the expelled exhaust gases.

4. How does the action and reaction law apply to fluids and gases?

In fluids and gases, the action and reaction law applies to the pressure exerted by the fluid or gas. For example, when a swimmer pushes against the water, the water exerts an equal and opposite pressure on the swimmer, propelling them forward.

5. Are there any known exceptions to the action and reaction law?

While the action and reaction law is considered a fundamental law of physics, there are some exceptions in certain cases. For example, at the quantum level, particles can exhibit behavior that appears to violate this law. However, these exceptions are still being studied and do not affect the validity of the law in macroscopic systems.

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