The condition for a uniform spherical mass `m` of a radius `r` to be a black hole is [`G` =gravitational constant and `g`=acceleration due to gravity]

Options

A. `sqrt(( 2 Gm )/(r)) le c`
B. `sqrt ((2 Gm )/(r) ) =c`
C. `sqrt ((2 Gm )/(r) ) gec`
D. `sqrt ((Gm )/(r) ) gec`

Answer

C

Explanation

Escape velocity of that body
`v_(e) = sqrt((2 G m )/( r))`
`v _(e)` shoudld be more than or equal to speed of light `i.e. sqrt ((2 G m )/r)ge c`