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B Dropping a Black Hole from Tower of Piza

  1. Oct 15, 2016 #1
    I get that if you drop a tennis ball and a 10 lb medicine ball from the top of a tower they will both reach the ground at the same time. But what if I dropped a softball and a black hole with the radius of a softball (and the mass of a small planet)? Wouldn't the tremendous gravity of the black hole pull that much harder on the Earth, thereby closing the gap between them faster than the gap between the Earth and the softball?
  2. jcsd
  3. Oct 15, 2016 #2


    Staff: Mentor

    What does Newton's second law say about the acceleration of the BH?
  4. Oct 21, 2016 #3


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    Science Advisor

    Does the answer bother you?
    What are the assumptions in the statement "all objects fall at the same acceleration"?
    Are the assumptions still valid here?
  5. Oct 21, 2016 #4

    Vanadium 50

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    2017 Award

    The softball would fall into the black hole, and not down.
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