
#1
Sep1313, 06:46 AM

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all objects travel at a speed .when we come to light , the speed is approximately 3 * 10^{8} . i am confused about how can it travel with such a speed . i have surfed in the internet but it only says that it is not yet proved . i wish to know the answer . this could help me to study optics more perfectly . did Einstein prove in the theory of relativity.




#2
Sep1313, 06:58 AM

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The speed of light has been measured numerous times and the speed measured is approx. 3*10^8 m/s. The speed of light in a vacuum is a fundamental constant in physics. The rest of your ramble makes no sense.




#3
Sep1313, 07:14 AM

P: 9





#4
Sep1313, 07:19 AM

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superfast lighthttp://en.wikipedia.org/wiki/Maxwell's_equations http://hyperphysics.phyastr.gsu.edu.../maxeq.html#c3 The speed of light falls naturally out of Maxwell's equations. There is simply no other speed at which it can travel through vacuum and still obey Maxwell's equations. 



#5
Sep1313, 07:20 AM

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It was Maxwell who demonstrated that EM waves travel at the speed of light, which can be expressed as a combination of other fundamental constants associated with electromagnetism (Einstein demonstrated that the speed of light is a universal speed limit).
We know the value of these fundamental constants from observation  by determining the force between two charges etc. Claude. Edit: beaten by Dale! 



#6
Sep1313, 07:26 AM

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#7
Sep1313, 07:48 AM

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I confused about what you're confused about. What is the question? Light travels at a certain speed. That speed has been measured to be about 3 * 10^8 m/s. What don't you understand?




#8
Sep1313, 09:46 AM

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From the FAQ section of our relativity forum:
Why does c have a particular value, and can it change? 



#9
Sep1313, 09:58 AM

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If you want to understand the behavior of light, your best bet may be to try to forget that you ever heard the word "photon", and work your way through the classical model of light as an electromagnetic wave instead. You can go back to thinking about photons when you're ready to move beyond classical physics and take on quantum mechanics. 



#10
Sep1313, 12:01 PM

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And the analogy with hitting a ball is very puzzling. This is because it requires the bat to impart energy and momentum (speed) to the object. This is not true with light since the photons are born at c. Zz. 


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