# quick blackhole question.

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There is something i dont quite understand. Maybe this is just a newb question so flame away but, here goes. How do black holes "suck in" light, if it has no mass? Or does it have mass? I googled this but didnt really find anything, so if anyone could explain this in a easy-to-understand way ( thats right, imagine your talking to an idiot =P ) id be grateful.

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There is something i dont quite understand. Maybe this is just a newb question so flame away but, here goes. How do black holes "suck in" light, if it has no mass? Or does it have mass? I googled this but didnt really find anything, so if anyone could explain this in a easy-to-understand way ( thats right, imagine your talking to an idiot =P ) id be grateful.

Gravity does affect the trajectory of light, by warping space; the Newtonian equation relating to mass turns out to only be an approximation. In a black hole the warping means that the trajectory is changed so much that the light curves back in on itself.

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inside a black hole all directions lead to the centre

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K, i guess while im at it, might as well post yet another stupid question. Nothing can travel at the speed of light except light right? But, when matter is pulled into a black hole with a force that is faster than the speed up light, isnt it being excelerated to the speed of light, of not, even faster? And what happens to it when it does? Thx in advance. Btw, i did look in wikipedia lol, and while it did have alot of info, didnt find exactly what i was looking for.

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It's not being pulled into the black hole faster than the speed of light. Matter can be accelerated to quite phenomenal speeds, sometimes close to the speed of light, prior to entering the black hole, but it's not going at light speed or any faster.

Why?

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Because matter cannot travel at or beyond lightspeed. Why would it, anyway?

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Ok, i guess i confused myself. I just assumed that if it was being pulled by a force faster than light, that thats the speed it would travel at.

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what do you mean being pulled by a force faster than light?

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the foce only provides an acceleration for the object not a speed. s

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In order to escape a gravitational pull you need to reach escape velocity. The greater the gravitational force pulling you down, the larger that speed has to be. OK?

In a black hole, the event horizon is the point at which the escape velocity is greater than the speed of light. And since nothing can travel faster than the speed of light, nothing can escape once past the event horizon (including light).

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Ok, i guess i confused myself. I just assumed that if it was being pulled by a force faster than light, that thats the speed it would travel at.

Gravity isn't faster than light.

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i don't think its going any faster at all. It may seem faster to us but a black hole is just warped space. So its going the same speed all the time in the space that it is in.

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