If a black hole is truly black and has an escape velocity greater than the speed of light such that no light can escape it, where do the x-rays come from in the black hole candidates so far identified?

Explanation:

The X- rays are not emitted by the black hole itself but by the  from hot gas orbiting around the black hole forming a disc known as accretion disk. When a black hole rips apart a star it attracts gases towards it. The pressure that is generated in the gas heats it up to millions of degrees thus emitting radiation among which x rays are also present which are detected by radio telescopes on the earth.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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