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Deepanshu Chaudhary Asked a Question
April 22, 2020 4:58 pmpts 30 pts
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According to the postulate of special theory of relativity, speed of light is constant in vacuum. but in other media, there are particles that can travel faster

According to the postulate of special theory of relativity, speed of light is constant in vacuum. But in other media, there are particles that can travel faster than speed of light in that medium which is also known as Cherenkov radiation. So in that case, if a particle is moving with a velocity v in the direction of light, will the speed of light for that particle as frame of reference be c-v or c. Here, c is the speed of light in that medium
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  • Abhishek singh
    Untill now, nothing physical can exceed speed of light according to Einstein's theory of relativity.
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    Deepanshu Chaudhary
    ya that's in vacuum. but in other media light slows down right.
  • Deepanshu Chaudhary
    @Rubiiii mam can you go through this explanation please. According to it, electrons can travel faster. So in that case, according to the formula of velocity addition. The speed of ...
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  • Shanu arora thankyou
    solution : here is the solution where I have consider both the cases 1) particle also in medium 2) particle in lab frame. the formule used is for finding relative velocity in relat...
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    Deepanshu Chaudhary
    Yes. the second case is what I'm asking about. So, according to the formula, the velocity of light in that medium wrt to the particle should decrease
  • Ruby negi
    No,, there is no particle(except tycoon which is still not discovered)having velocity greater than speed of light . Cherenkov radiation are those when light passes through a diele...
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  • Ruby negi thankyou
    speed of light remain same in all inertial frames.. when light passes through medium then speed of light in that medium decrease and that is c/(refractive index of that medium)
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  • Abhishek singh Best Answer
    it's phase velocity, which may exceed speed of light in some media, without violating relativity. Phase velocity is not physical. it is hypothetical (just theoretical, nothing phys...
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