Question

what is a black hole???? explain types of black hole.

Answer 1

Black Hole is the region of very large gravitational field that pulls everything inside it.Even light can't escape its wrath.

A Black Hole is formed when a star at the stage of Supernova or we can say when it is dying collapses under its own large weight at the center.This collapse leads to huge explosion of the star and the parts of the stars are thrown into space.

A Black hole can't be seen. It absorbs all the sources of light,hence there is no source of light to be reflected back so that they can be seen.
Albert Einstein was the  first to explain about black holes using his famous "General Theory of Relativity".
The term was given by John Wheeler.

The first black hole was discovered in 1971

Coming to the types of Black Holes -->
They are basically of three types
1) Stellar
2)Supermassive
3) Intermediate

STELLAR MASS BLACK HOLES

This is the usual type of black hole. Stellar black holes form when the star at the Supernova stage collapses under its own weight at its center.The pieces of star may be thrown into space or may fall into the black hole.This may cause the black hole to be more heavy.The collapse of star occurs due to nuclear reactions.The radiations causes the star to expand and expand and at last it bursts and gravity makes the star to collapse.

SUPERMASSIVE BLACK HOLES

These are one of their kind black holes. A supermassive black hole is the largest black hole ever formed. It is rare and not found in every galaxy. According to current known black holes, these type of black holes are found in large galaxies only.It is billion even gazillion times larger than stellar mass black holes. The presence of supermassive black holes was identifies by locating some pieces of material orbiting in the center of large galaxies.
The Milky Way galaxy also has one Supermassive Black Hole in the center, Sagittarius A*

INTERMEDIATE BLACK HOLES

There are like medium sized black holes.It is believed that intermediate black holes may have lead to supermassive black holes.But this hasn't been confirmed yet.These are greater than steller mass ones but smaller than supermassive ones.They are believed to be formed at star dense areas the globular clusters.Scientists have searched these globular clusters but the black holes were not identified.


Scientists have said that black holes can exist at any mass - small , medium, large, anything.The quest to know about black holes still continues.

 

Answer 2

A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.