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Old 05-16-2008, 10:12 AM
sorincosofret sorincosofret is offline
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Default Lifts experiments and equivalence principle

Due to the impossibility of picture display in the forum, a more complete presentation is made on:
elkadot.com/relativity.html

The description of experiments:

Experiment 1.

Two lifts one situated in gravitational field and another one in an acceleration field are considered like in fig. 2.9
On every lift a golf player having a device for ball throwing is considered.
In case of gravitational field when the device throws the ball with an angle α, the trajectory of ball is a known parabola. After the y axis the ball moves for a time upward and after that downwards related to the floor of lift considered as reference.
In second case, when the machine throws the ball with the same angle α, the trajectory of ball is always upwards. The observer having already an idea of the place where the ball must fall will observe the curios trajectory of ball. Without applying any mathematical formula he will deduce a simple and logical conclusion. There is a fundamental difference between a gravitational field and an acceleration field and is impossible to have an equivalence of them. It is possible in some cases to have the same effect in both cases, but theoretically an infinity of causes can produce the same effect.

Experiment 2

The same frame with two lifts is considered like in fig 2.10 but in every lift there is a hunter having a fire arm and there is a possibility to measure the impact energy of bullets.
In every case, for every lift, the hunter will measure this impact energy for a horizontal bullet (E1) and for a vertical bullet (E2).
After that, the observer from every lift, compare the impact energy of bullets thrown in vertical direction with the energy for a bullet thrown in horizontal direction.
In case of a gravitational field, there will be a significant difference between this energies and ΔE = E2 - E1 will be different of zero, due to the fact that gravitational field modify the kinetic energy of bullet with different amounts in up presented cases.
In case of accelerating field, the observer will measure the same impact energy in both cases, more precisely E1=E2.
In case of closed observer, the throwing a bullet in this field means a action of gravitation in a specific manner of moving bullets. In case of a accelerated field of force the energy in both cases (vertical and horizontal) is the same, only the trajectory of bullets is apparent modified by accelerated field.
Again there is impossible to make the assumption of equivalence between an accelerated field and a gravitational filed.
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Old 06-27-2008, 11:23 AM
HallsofIvy HallsofIvy is offline
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Default

Quote:
Originally Posted by sorincosofret
Due to the impossibility of picture display in the forum, a more complete presentation is made on:
elkadot.com/relativity.html

The description of experiments:

Experiment 1.

Two lifts one situated in gravitational field and another one in an acceleration field are considered like in fig. 2.9
On every lift a golf player having a device for ball throwing is considered.
In case of gravitational field when the device throws the ball with an angle α, the trajectory of ball is a known parabola. After the y axis the ball moves for a time upward and after that downwards related to the floor of lift considered as reference.
In second case, when the machine throws the ball with the same angle α, the trajectory of ball is always upwards.
How do you arrive at that? With no gravitational force, the ball will have constant velocity. The lift, since it has constant acceleration, will eventually be going upward faster than the ball. An observer standing in the elevator will see the ball go up at first, then come down. It is easy to calculate that the constant acceleration will give the same parabolic trajectory as a constant gravitational force.

Quote:
The observer having already an idea of the place where the ball must fall will observe the curios trajectory of ball. Without applying any mathematical formula he will deduce a simple and logical conclusion. There is a fundamental difference between a gravitational field and an acceleration field and is impossible to have an equivalence of them. It is possible in some cases to have the same effect in both cases, but theoretically an infinity of causes can produce the same effect.
And you believe that just SAYING that makes it so? Where are your calculations?

Quote:
Experiment 2

The same frame with two lifts is considered like in fig 2.10 but in every lift there is a hunter having a fire arm and there is a possibility to measure the impact energy of bullets.
In every case, for every lift, the hunter will measure this impact energy for a horizontal bullet (E1) and for a vertical bullet (E2).
After that, the observer from every lift, compare the impact energy of bullets thrown in vertical direction with the energy for a bullet thrown in horizontal direction.
In case of a gravitational field, there will be a significant difference between this energies and ΔE = E2 - E1 will be different of zero, due to the fact that gravitational field modify the kinetic energy of bullet with different amounts in up presented cases.
In case of accelerating field, the observer will measure the same impact energy in both cases, more precisely E1=E2.
In case of closed observer, the throwing a bullet in this field means a action of gravitation in a specific manner of moving bullets. In case of a accelerated field of force the energy in both cases (vertical and horizontal) is the same, only the trajectory of bullets is apparent modified by accelerated field.
Again there is impossible to make the assumption of equivalence between an accelerated field and a gravitational filed.
And, once again, you simply SAY that without actually doing any calculations.
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