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Thread: What is the Schwarzchild Radius of a 1 billion Solar mass object?

  1. #1 What is the Schwarzchild Radius of a 1 billion Solar mass object? 
    The Doctor Quantime's Avatar
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    Thanks!


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    Quantime, no homework questions!

    But you'll find a sufficient answer here:
    Yahoo! Canada Answers - What would be the Schwarzschild radii of black holes of 1 million and 1 billion solar masses?



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  4. #3  
    Forum Bachelors Degree x(x-y)'s Avatar
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    Well, the formula for the Schwarzschild radius is



    where 2G/c^2 is a constant so all you need is the mass - which is 1Bn solar masses in this case. So just plug 1Bn multiplied by ~2x10^30 kg into the formula, making sure to use S.I. units for G and c, and you'll get your answer.
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    Forum Ph.D. merumario's Avatar
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    This is also called gravitational radius,distance that defines the size at which a spherical astronomical object such as a star becomes a black hole.
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    Forum Ph.D. merumario's Avatar
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    The formular for this radius is Rs=GM/c^2,where Rs is the schwarszchild radius,G is constant known as universal gravitational constant,M is mass of the object.
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    Forum Ph.D. merumario's Avatar
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    The formular for this radius is Rs=GM/c^2,where Rs is the schwarszchild radius,G is constant known as universal gravitational constant,M is mass of the object, c is the speed of light.
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    Quote Originally Posted by merumario View Post
    The formular for this radius is Rs=GM/c^2,where Rs is the schwarszchild radius,G is constant known as universal gravitational constant,M is mass of the object, c is the speed of light.
    It appears you have provided the wrong answer - twice.
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  9. #8  
    Forum Ph.D. merumario's Avatar
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    Harold i truely doubt that...can you show the right equation? And please not that by 'xy' because there is no mass,and i do not see where it becomes 2G. I think that expression is more like the escape velocity equation provided by laplace.
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    The Doctor Quantime's Avatar
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    No homework it was my own adventure this one Thanks guys I did work it out in the end, my final question was answered based on one of my projects. I got a Schwarzchild Radius of 34 Light Years
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  11. #10  
    Moderator Moderator Janus's Avatar
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    Quote Originally Posted by Quantime View Post
    No homework it was my own adventure this one Thanks guys I did work it out in the end, my final question was answered based on one of my projects. I got a Schwarzchild Radius of 34 Light Years
    You might want to check that answer. A solar mass black hole has a radius of only 3 km, and the BH radius is proportional to the mass. That make a 3 billion km radius for a 1 billion solar mass BH, and even if you are using the "long scale" billion (1e12) that still only works out to ~a third of a light year.
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    Moderator Moderator Markus Hanke's Avatar
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    The Schwarzschild radius of an object, in terms of multiples of solar masses, is



    The Schwarzschild radius of a 1 billion solar mass object is thus 2.95 billion kilometers. The largest known supermassive black hole sits in the center of a galaxy with the designation NGC 4889, and weighs in at a whopping 17-21 billion solar masses ( approximately ). Just to get a sense of scale - if you were falling from the event horizon ( starting at rest ) into that black hole, your total infall time as experienced by yourself would be roughly 80 hours, meaning you would fall for over three days before hitting the singularity. Interestingly, for a BH of that scale the tidal forces on your body would be quite small - you would in fact survive until just before reaching the singularity.
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  13. #12  
    The Doctor Quantime's Avatar
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    Quote Originally Posted by Janus View Post
    Quote Originally Posted by Quantime View Post
    No homework it was my own adventure this one Thanks guys I did work it out in the end, my final question was answered based on one of my projects. I got a Schwarzchild Radius of 34 Light Years
    You might want to check that answer. A solar mass black hole has a radius of only 3 km, and the BH radius is proportional to the mass. That make a 3 billion km radius for a 1 billion solar mass BH, and even if you are using the "long scale" billion (1e12) that still only works out to ~a third of a light year.
    Thanks, what I ended up doing was using ridiculous values though purely hypothetical
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