# Object falling into the sun

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

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Staff Emeritus
2019 Award
Not even close. It would impact at about 600 km/s.

DaveC426913
Gold Member
Not even close.

[ EDIT You're fast! ]

DaveC426913
Gold Member
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?

• Stephanus
pbuk
Gold Member
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.

A= GM/r^2

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

That's pretty fast, does this not apply?

Staff Emeritus
2019 Award
Acceleration is not velocity. And your calculation has wrong numbers in it.

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).

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.

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.

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.