Explanation:

A black hole is a region in space that has an extremely strong gravitational pull, so strong that nothing, not even light, can escape from it. The property of not allowing any radiation to come out is due to its extremely high density.

Understanding Density:

Density is a measure of how much mass is packed into a given volume. It is calculated by dividing the mass of an object by its volume. In the case of a black hole, the mass is concentrated within a very small volume, resulting in an incredibly high density.

Formation of a Black Hole:

Black holes are formed from the remnants of massive stars that have undergone a supernova explosion. When a massive star exhausts its nuclear fuel, it undergoes gravitational collapse. The core of the star collapses under its own gravity, and if the mass is sufficient, it will form a black hole.

Gravitational Collapse:

During the gravitational collapse, the matter in the core of the star becomes extremely compressed. As the core collapses, the gravitational force becomes stronger, pulling matter inward. This intense gravitational force causes the matter to become denser and denser, eventually reaching a point where the density is so high that nothing can escape its gravitational pull, not even light.

Event Horizon:

The point of no return, beyond which nothing can escape, is called the event horizon. It is the boundary of the black hole, beyond which the gravitational pull is so strong that even light cannot escape. The event horizon is determined by the mass of the black hole, and the smaller the size of the black hole, the stronger its gravitational pull and the smaller its event horizon.

Conclusion:

In conclusion, the property of a black hole not allowing any radiation to come out is due to its extremely high density. The mass of a black hole is concentrated within a very small volume, resulting in a gravitational pull so strong that nothing, not even light, can escape its grasp. This property is independent of the size or density of the surrounding space, but rather is a result of the immense density within the black hole itself.