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Black Holes Gre.67

  1. Nov 30, 2003 #1
    Black Holes Gre.67
    67. A black hole is an object whose gravitational field is so strong that even light cannot escape. To what approximate radius would Earth (mass = 5.98 x 10^24

    kilograms) have to be compressed in order to become a black hole?
    a. 1 nm
    b. 1 microm
    c. 1 cm
    d. 100 m
    e. 10 km

    the answer is C.
  2. jcsd
  3. Nov 30, 2003 #2


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    [tex]r_s = \frac{2 G M}{c^2}[/tex]

    - Warren
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