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]

  • A

    ${(2Gm/r)^{1/2}} \le c$

  • B

    ${(2Gm/r)^{1/2}} = c$

  • C

    ${(2Gm/r)^{1/2}} \ge c$

  • D

    ${(gm/r)^{1/2}} \ge c$

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