It is known that radius of black hole is 2GM/c^2. And second radius is 3GM/c^2. (light ray at the second radius is not eaten but it circulate around black hole.)(adsbygoogle = window.adsbygoogle || []).push({});

But, let us assume that we have body which moves almost with speed of light.

1. Are these two radiuses the same or approximately the same?

Let as assume Light-ray which come from infinity and come close to one body from distance (27)^(1/2) GM/c^2. If this body is changed to black hole, black hole will affect this light-ray that he wil come 3GM/c^2 close to it. And after this it will stay close to black hole, as described above.

2. question, if this is very fast body (not light-ray) is calculation the same?

BR

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# Black hole radius

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