Black Hole
Black hole is a thing which attract everything of the universe which is nearest to it and engulf the thing inside it. If we throw a thing upside then it will come back to the downward, this happens due to the gravitational force of the earth. If we have to throw the thing out of the gravitational pool of the earth than we have to give some energy and velocity to the thing, suppose we are standing in an open field and we threw the thing with some energy and velocity through which the thing can go out of the earth's gravitational pool and that velocity is called escape velocity . Now the question arises ,i.e., Whom does the escape velocity depends on? ANS- Escape velocity depends upon the mass of the earth and size of the earth. And we know that moon is smaller than earth on behalf of size, so the escape velocity of moon is lesser than earth that is why there is no atmosphere because the gases of ...