And what was the relative speed between the light beam and the plane?
Light at Light Speed
- Thread starter Bowser
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O = Plane and light both start from Earth
A = Light arrives at sun
B = Plane at the same time as A as seen from Earth
D = Plane at the same time as A as seen from Plane
C = Earth at the same time as A as seen from Earth
E = Earth at the same time as A as seen from Plane
Already answered two different ways:
$$\frac{\Delta x'}{\Delta t'} = \frac{x'_A - x'_O}{t'_A - t'_O} = \frac{ \left. \quad \frac{\sqrt{3} L }{ 3 } \quad \right. }{ \left. \quad \frac{\sqrt{3} L }{ 3 c } \quad \right. } = c$$
$$f_{\frac{1}{c^2}}(c, \frac{c}{2}) = \frac{c - \frac{c}{2}}{1 - \frac{1}{c^2} \times c \times \frac{c}{2}} = \frac{c - \frac{c}{2}}{1 - \frac{c^2}{2 c^2}} = \frac{ \left. \quad \frac{ c }{ 2 } \quad \right. }{ \left. \quad \frac{ 1 }{ 2 } \quad \right. } = c$$
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So after 8 minutes spent on the Earth the plane is at a distance $$\frac{\sqrt{3} L}{6}, \$$
After another eight minutes spent on Earth, how much will be the distance?
Sorry.
The Michelson-Morley Experiment
Quote from the URL:
The null results obtained by Michelson and subsequent experimenters showed that the ether hypothesis was incorrect. The speed of light did not depend on the motion of the source, as had been widely assumed.
Sorry I did not get back to this thread sooner. Rpenner - thanks for answering Emils question.
There's no way to answer that until you say who is keeping track of the time and who is keeping track of the distance.
From A - O, Earth sees the elapsed time as $$\Delta t = t_A - t_O = \frac{L}{c}$$ which if L is 8 light-minutes, then this time is 8 minutes on Earth.
But the plane sees the time as $$\Delta t' = t'_A - t'_O = \frac{\sqrt{3} L}{3 c}$$ which would be about 4 minutes and 37 seconds on the plane.
After 8 minutes on the Earth, the distance between the plane and the Earth is, using Earth rulers, $$\Delta x = x_B - x_C = \frac{L}{2}$$ or 4 light-minutes.
After about 4 minutes and 37 seconds on the plane, the distance between the plain and the Earth is, using plane rulers, $$\Delta x' = x'_D - x'_E = \frac{\sqrt{3} L}{6}$$ which is about 2.3 light-minutes.
After 8 minutes on the Earth, the distance between the plane and the Earth is, using plane rulers, $$\Delta x' = x'_B - x'_C = \frac{\sqrt{3} L}{3}$$ or 4.6 light-minutes, but because B and C don't happen at the same time for the plane, this distance is between where the plane is at time B and where the Earth will be at time C, according to the plane.
You would do yourself a favor if you drew a graph of x vs. t and labeled the points O, A, B, C, D, E and drew straight lines for the movement of the light, the movement of the plane and the (non-)movement of the Earth, and then drew a different graph of x' vs. t' to see O, A, B, C, D, E from the plane's clocks and rulers.
I agree with that.
But who talked about ether? Lorentz did it?
We talked about time dilation, length contraction and about the speed of propagation of light
What is your opinion about these?
Michelson-Morley experiment,Length contraction:
Recent experiments:
Special relativity,Postulates:
How do you interpret the following sentence?:
That is, light in vacuum propagates with the speed c (a fixed constant, independent of direction) in at least one system of inertial coordinates (the "stationary system"), regardless of the state of motion of the light source.
So, after 16 minutes measured on Earth and according to the Earth the plane reaches the Sun.(The plane has the same coordinates as the Sun.)
So, after 27,7 (27min 42sec) minutes measured on Earth and according to the plane, the plane reaches the Sun.(The plane has the same coordinates as the Sun.)
This means that if the plane "back" from the Sun,
it will "land" on Earth after 32 minutes from departure, according to the Earth,
and it will "land" once again after 55.4 minute (55min, 24sec) from departure, according to the plane.
Right?
No shift in the fringe pattern was seen from the relative motion between the light source and the apparatus, indicating that there was no affect on the relative speed of light. So this conforms with special relativity and the affects of time dilation and length contraction.
A negative result was seen, that is, relative velocity had no affect on the speed of light, indicating that time dilation and length contraction were in evidence.
I interpret this as meaing that if you are stationary relative to a moving light source that the speed of light from that source will always be measured by you as c.
This is event S. $$\left( x_S = x_O + L , \quad t_S = t_O + \frac{2 L}{c} \right)$$. The same event is seen by the plane as: $$\left( x'_S = x'_O , \quad t_S = t_O + \frac{\sqrt{3} L}{c} \right)$$.
No. The plane reaches the sun once and only once. And the time that takes is $$\Delta t = t_S - t_O = \frac{2 L}{c} $$ or 16 minutes on Earth clocks.
The time that takes by plane clocks is: $$\Delta t' = t'_S - t'_O = \frac{\sqrt{3} L}{c} $$ or about 13 minutes 51 seconds on plane clocks.
If you mean from Earth's perspective, upon reaching the sun the plane immediately heads to the Earth with uniform speed of c/2, the velocity of the plane on the return trip is not the same as the velocity of the plane on the trip to the sun. So you need to use new symbols to differentiate old plane coordinates (x', t') from new plane coordinates (x'', t'').
So for Earth, the event of the return R happens with coordinates $$\left( x_R = x_S - L = x_O, \quad t_S = t_S + \frac{2 L}{c} = t_O + \frac{4 L}{c} \right)$$ and for the new plane clocks and rulers, this is:
$$\left( x''_R = x''_S, \quad t''_R = x''_S + \frac{\sqrt{3} L}{c} \right)$$.
$$\Delta t_{\textrm{Earth}} = \Delta t_{S-O} + \Delta t_{R-S} = t_S - t_O + t_R - t_S = t_R - t-O = \frac{4 L}{c}$$ which is 32 minutes.
$$\Delta t_{\textrm{Plane}} = \Delta t'_{S-O} + \Delta t''_{R-S} = t'_S - t'_O + t''_R - t''_S = \frac{\sqrt{3} L}{c} + \frac{\sqrt{3} L}{c} = \frac{2 \sqrt{3} L}{c} $$ which almost 27 minutes 43 seconds.
The people on the plane are now 4 minutes and 17 seconds younger than they would have been had they remained on Earth. They had 4 minutes 17 seconds less time to listen to music or to worry about the plane losing oxygen or burning up on the trip compared to people on the ground.
If a single experiment has spent so much then you can you have a hunch of the size of funds involved?
I am aware that they will never admit they're wrong.
Therefore, it is so important the opinion of the scientific community
and not only the opinion of specialists directly involved.
I think the following link clear up the situation:
95 Years of Criticism of the Special Theory of Relativity (1908-2003)
I think you are saying "the situation" is that you are a nutter.
Special relativity is what allows us to talk about the mass of the electron without specifying a state of motion and a direction of force.
Nothing in your link argues against special relativity.
Special relativity is what allows us to talk about the mass of the electron without specifying a state of motion and a direction of force.
Nothing in your link argues against special relativity.
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I asked a simple question: After eight minutes measured on Earth, at what distance is the plane?
You can not give an answer. Is L/2 or $$\frac{\sqrt{3} L}{6} \$$?
You asked:
From the Earth towards the Sun, starts simultaneously , a plane at speeds of V1=150,000 km/s and a short beam of light at speed of V2=300,000 km/s
In about eight minutes the light beam reaches the Sun.
At this moment the plane is halfway between Earth and Sun.
This is not correct?
As measured from the reference frame of earth that is correct.
For Earth rulers and clocks, C, B, and A happen at the same time.
canvas_sigma by PhysForum Photos, on Flickr
For the outbound plane's rulers and clock, E, D, and A happen at the same time.
canvas_sigma_prime by PhysForum Photos, on Flickr
canvas_sigma by PhysForum Photos, on Flickr
For the outbound plane's rulers and clock, E, D, and A happen at the same time.
canvas_sigma_prime by PhysForum Photos, on Flickr
That is exactly what I said. You are not able to give an answer. What is the distance?For Earth rulers and clocks, C, B, and A happen at the same time.
canvas_sigma by PhysForum Photos, on Flickr
For the outbound plane's rulers and clock, E, D, and A happen at the same time.
canvas_sigma_prime by PhysForum Photos, on Flickr
Say a number and unit. Or proportion.
rpenner,
You agree with that?
Yes, I agree that the phrase "At this moment" requires one to specify whose clocks are being used. You have not argued against this.
Your complaint about my inability to answer your ill-posed questions does not render them better phrased nor does it contradict my assertion that they are not clearly asked.
Your complaint about my inability to answer your ill-posed questions does not render them better phrased nor does it contradict my assertion that they are not clearly asked.
I did not explicitly state that the clock I was going by was the clock in the earths inertial frame - which I should have done.
origin, I saw your thinking evidenced your post and do not fault it.
But, my experience is that to assume that everyone who asks questions on the Internet is being honestly ignorant as opposed to willfully and dishonestly ignorant is to set yourself up for grief. So I let the evidence build up out of fairness to the honest, ignorant, and stupid lest I accuse those whose questions the dishonest ape, and I resist the efforts of the questioner to shape my answers to reduce the errors introduced into the discussion.
So now, the question has been answered in algebra and geometry and in English and all three answers are the same: knowing whose clocks and rulers are being used is crucial to answering questions about distance and situations which happen at the "same time."
But, my experience is that to assume that everyone who asks questions on the Internet is being honestly ignorant as opposed to willfully and dishonestly ignorant is to set yourself up for grief. So I let the evidence build up out of fairness to the honest, ignorant, and stupid lest I accuse those whose questions the dishonest ape, and I resist the efforts of the questioner to shape my answers to reduce the errors introduced into the discussion.
So now, the question has been answered in algebra and geometry and in English and all three answers are the same: knowing whose clocks and rulers are being used is crucial to answering questions about distance and situations which happen at the "same time."
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this paper quotes many, Deutsche Physik (translated: aryan physics) journals and is one of the most hated filled, anti semitic intellectual movements in German history, ending in the Nazi party. just so you know it's not fact but propaganda.
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