GravitationMedium
Question
The condition for a uniform spherical mass m of radius r to be a black hole is :[G =gravitational constant and g = acceleration due to gravity]
Options
A.

B.

C.

D.

Solution
A black hole does not allow light to escape its surface. In other words for a blackbody escape velocity becomes ≥ velocity of light
Now for a body of mass m,
Escape velocity =
So, =
Now for a body of mass m,
Escape velocity =

So, =

Create a free account to view solution
View Solution FreeMore Gravitation Questions
A satellite is seen after each 8 hours over equator at a place on the Earth when its sense of rotation is opposite to th...Three particles projected vertically upward from a point on the surface of the Earth with velocities,,, respectively whe...If the distance between the centers of Earth and Moon is D and mass of Earth is 81 times that of Moon. At what distance ...A particle is projected from point A, that is at a distance 4R from the centre of the Earth, with speed v1 in a directio...A body of mass ′m′ is taken from the earth′s surface to the height equal to twice the radius (R) of th...