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michelson M. question?? (1 Viewer)

jzi

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undefined
what is the significanceog the michelson- morley experiment?
what inference did einstein make??
 

serge

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they practically spell it out in the syllabus
or just go to HSC online

and you shouldnt worry about it got a whole year to find out
 

Rekkusu

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Lol definitely ^^ You're quite lucky to have a whole year ahead of you. Its always better to start preparing in Year 11, saves you a countless number of hours...

Though, since this is good practice for my hsc, I'll state it out briefly:

The Michelson & Morley experiement was designed specifically in order to test for the existence of an Aether / Ether, which was believed to be a medium in which it filled all space and was stationary in space, it completely permeates all matter, has a low density and is also able to propagatate light waves easily. Basically they believed that light being a waveform required such a medium.

In the end, they could not prove the existence of Aether..
 

Haku

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Rekkusu said:
Lol definitely ^^ You're quite lucky to have a whole year ahead of you. Its always better to start preparing in Year 11, saves you a countless number of hours...

Though, since this is good practice for my hsc, I'll state it out briefly:

The Michelson & Morley experiement was designed specifically in order to test for the existence of an Aether / Ether, which was believed to be a medium in which it filled all space and was stationary in space, it completely permeates all matter, has a low density and is also able to propagatate light waves easily. Basically they believed that light being a waveform required such a medium.

In the end, they could not prove the existence of Aether..
it was actually designed to test the speed of earth through the aether.
 

exa_boi87

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nosadness said:
it was actually designed to test the speed of earth through the aether.
Yep, the relative speed of the earth and the thought that aether wind would have an effect on the speed of light
 

Haku

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yea, also basing on that fact that aether is considered the constant frame of reference
 

Sonic

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basically it is that they proved that the aether did not exist..
einstein jsut put forth the idea that the ether did not need to exist... check the syllabus 4 more
 

Wakaveli

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Anecdotally, however, we must consider that when Einstein deemed the Aether model obsolete; he was unaware of the Michelson/Morley result - and made aware of it subsequent to his famous paper.
 

exa_boi87

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True .. his particle model of light meants that a substance such as the ether was not required to permeate all space in order for it to propogate. As such, concluded that this absolute frame of reference did not exist.

by the way, the negative result of MM didnt completely void the aether theory did it? ... I thought after this, it was thought the aether travelled "with" the earth
 

Abtari

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the negative result didn't dishearten ardent supporters of the aether model.. they tried countless times to prove its existence by way of detecting an 'aether wind'...

oh and btw, what does the particle model of light proposed by einstein (which is studied in ideas) have anything to do with the rejection of the aether model. einstein showed the redundancy of this model, through his idea of CONSTANCY of speed of light, not its particulate nature... lol unless i'm mistaken, you have got your modules mixed up.
 

wanton-wonton

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jzi said:
undefined
what is the significanceog the michelson- morley experiment?
what inference did einstein make??
Einstein didn't make any inference based on the results of the MM experiment.
Einstein, in fact, didn't consider the results of the MM at all when proposing his special relativity. (I think)

In other words, Einstein started from a whole different viewpoint.

What I'm not too pleased with is that many textbooks said that Einstein's proposal made the aether superfluous. However, since the speed of light is constant, then wouldn't that mean the aether is a wrong model and thus reject it altogether?
 
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Abtari

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bit off the topic but relevant still.

'discuss the principle of relativity'

someone pls help with this dotpoint...

oh, and what was the significance of einstein's assumption of constancy of speed of light

thanks
 
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KFunk

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Abtari said:
oh, and what was the significance of einstein's assumption of constancy of speed of light
The significance is that all that time dilation, length contraction, relativity stuff follows from that assumption. If you assume that the speed of light is constant relative to an observer then other quantities have to become variable. The derivation of time dilation which I quite like, for it's simplicity, is this one.

The gist of the argument is based on geometry. Observer 1 sees the light travel a certain distance cto from the top of the time clock to the bottom of the time clock. Observer 2 sees the light travel from the top to the bottom of the time clock as well but the time clock is also moving relative to him so light travels a diagonal (forming the hypotenuse of a right angled triangle). Simple geometry would say that observer 2 saw light travel a greater distance. Using galilean relativity we would assume that light was just travelling faster relative to him than it is relative to observer 1, but instead we have assumed the constancy of the speed of light thus forcing time to become variable.
 

Abtari

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ok cool. i hope we don't need to know these derivations, i don't think we do anyway. you mentioned galilean relativity - in my original post, i asked about the principle of relativity. are these related in any way? what is the principle of relaitivity? i am assuming it is not special relativity, which is a different concept?!
 

香港!

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^
Isn't the Principle of General Relativity: u can't measure ur motion by any experiment in an inertial frame of reference. first postulated by Galileo, then embodied by Newtons laws??
and the Principle of Special Relativity is Einstein's stuff w\ dilation and contraction...
 

Abtari

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i think ur talking about the general principle of relativity, not principle of general relativity lol :D
 

KFunk

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Abtari said:
ok cool. i hope we don't need to know these derivations, i don't think we do anyway. you mentioned galilean relativity - in my original post, i asked about the principle of relativity. are these related in any way? what is the principle of relaitivity? i am assuming it is not special relativity, which is a different concept?!
Well, quoting from the jacaranda text:

Galileo posed a simple idea, now called the 'principle of relativity', which states that all steady motion is relative and cannot be detected without reference to an outside point.
It's the idea that underpins all that basic Galilean style relativity we did in 'moving about' in the prelim course. If you remember it you had questions like 'Aircraft A is travelling north at v ms-1 and aircraft B is travelling east at u ms-1 - what is the velocity of B relative to A?'. The extension of the principle would then be that your observations of the velocity of other objects is relative to your own frame of reference.
 

香港!

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^ oh LoLz
hehehe
but isn't the Principle of General Relativity NOT in the HSC course??
Think I remember it not being in it..
 

tennille

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Only special relativity is in the syllabus.

Just to clarify things, general relativity relates to the curvature of space-time, black holes and binary pulsar systems.
 

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