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Homework Help: Acceleration part 4

  1. Apr 16, 2007 #1
    1. The problem statement, all variables and given/known data

    Is it possible that you could throw a stone with sufficient energy to cause it to escape the asteroid’s gravitational pull altogether.

    Do you think you would be able to throw the stone as fast as this?

    2. Relevant equations

    v= squre root of (2GM / R)

    where M is mass of the Earth
    R is the radius of the earth

    3. The attempt at a solution

    M= 5.98*10^24

    after calculation,

    v= 11181.966 m/s

    this is the speed required....for stone to escape the atmosphere.
    So it is not possible.

    [is this correct]
  2. jcsd
  3. Apr 16, 2007 #2

    D H

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    Staff Emeritus
    Science Advisor

    Your question asks about throwing a stone "with sufficient energy escape the asteroid’s gravitational pull altogether", but your solution references the Earth's mass and radius. Are you sure you are using the correct mass and radius (the Earth is not an asteroid)?
  4. Apr 16, 2007 #3
    density of asteroid is 4.0 × 10^3 kg m−3 (given in previous part of the quesiton).

    desnisty= mass/volume

    v= (4/3)*pi*R ^3....need R to calculate V

    4.0 × 10^3 kg m−3 * v = m

    using m and r of asteroid..i should be able to calculate escapte velocity .

    [is this correct method]
  5. Apr 16, 2007 #4


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    Homework Helper

    I would think you should be able to determine the radius of the asteroid based on what you've done in the other parts of this question.
  6. Apr 19, 2007 #5
    Radius calculation

    can you explain how you calculated the radius of the asteroid?
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