Object falling into the sun

  • #1
Does an object falling into the sun reach approximately the speed of light?
 

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  • #2
Vanadium 50
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Not even close. It would impact at about 600 km/s.
 
  • #3
DaveC426913
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Not even close.

[ EDIT You're fast! ]
 
  • #4
DaveC426913
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Not even close. It would impact at about 600 km/s.
Don't you have to know from how far it's falling to provide a value?
 
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  • #5
pbuk
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Don't you have to know from how far it's falling to provide a value?
No, assume infinity and look up the escape velocity.
 
  • #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?
 
  • #7
Vanadium 50
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Acceleration is not velocity. And your calculation has wrong numbers in it.
 
  • #8
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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?
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).
 
  • #9
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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).
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
 
  • #10
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Don't you have to know from how far it's falling to provide a value?
I think if you drop it infinitely, it's the escape velocity.
 
  • #11
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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
No, that formula is an acceleration and not a velocity.
I did not say anything about Vanadium's post.
 
  • #12
DaveC426913
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I think if you drop it infinitely, it's the escape velocity.
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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