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Object falling into the sun

  1. Dec 27, 2015 #1
    Does an object falling into the sun reach approximately the speed of light?
     
  2. jcsd
  3. Dec 27, 2015 #2

    Vanadium 50

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    Not even close. It would impact at about 600 km/s.
     
  4. Dec 27, 2015 #3

    DaveC426913

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    Not even close.

    [ EDIT You're fast! ]
     
  5. Dec 27, 2015 #4

    DaveC426913

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    Don't you have to know from how far it's falling to provide a value?
     
  6. Dec 27, 2015 #5
    No, assume infinity and look up the escape velocity.
     
  7. Dec 28, 2015 #6
    What about this calc

    A= GM/r^2

    A= 10^-11 10^30 / 10^12
    = 10^7

    That's pretty fast, does this not apply?
     
  8. Dec 28, 2015 #7

    Vanadium 50

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    Acceleration is not velocity. And your calculation has wrong numbers in it.
     
  9. Dec 28, 2015 #8
    You are trying to calculate the gravitational acceleration on the "surface" of the Sun.
    If you do it correctly you will get about 300 m/s^2.

    But this is not a speed anyway. You cannot compare this with the speed of light (or any speed).
     
  10. Dec 28, 2015 #9
    https://en.wikipedia.org/wiki/Sun
    I think it's the escape velocity. If you put it infinitely. I'm no physicist, just using logic.
    Vanadium is right
     
  11. Dec 28, 2015 #10
    I think if you drop it infinitely, it's the escape velocity.
     
  12. Dec 28, 2015 #11
    No, that formula is an acceleration and not a velocity.
    I did not say anything about Vanadium's post.
     
  13. Dec 28, 2015 #12

    DaveC426913

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    Yes, I was about to follow up with the assumption that it falls from infinity.
    Even if it doesn't, that still acts as the upper limit of final velocity.
     
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