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Falling into a Volcano.

  1. Dec 9, 2011 #1
    Recently, there has been an argument of whether or not you would sink if you were unlucky enough to fall into a volcano. The proponents of this argument focus their attention on the water/magma density difference. Since the human body consists of 60-70% water, and water is less dense than magma, the proponents of this argument conclude that you would not sink. Rather, you'd act like a water balloon hitting a wall. However, the argument neglects to mention such things as composition, acceleration due to gravity, and the extreme heat.

    My contention is that the force of gravity, as one fell from the cone, would be sufficient enough to break the surface tension of the magma and sink. Additionally, as the body sank, the water would be drive off and the elements in the body would very quickly become part of the composition of the magma. Also, the gaseous component of the magma would allow for us to sink more readily depending on the abundance.

    Here's the site for the argument:


    What do you guys think?
  2. jcsd
  3. Dec 10, 2011 #2


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    Staff: Mentor

    Sounds like an archeology / anthropology question. "When humans were sacrificed to the gods by being thrown into a volcano, did they sink or did they float?"

    Likely there are still some cultures where larger animals (e.g., pigs) are sacrificed in the boiling magma cauldron.
  4. Dec 10, 2011 #3
    Might depend a lot on whether or not it has developed a crust.. The non-glowing crust would be rock hard.
  5. Dec 10, 2011 #4
    @ NascentOxygen, Umm, it may be my fault for not articulating the question well enough but, what I'm interested in is whether or not a body would sink if that same body were unfortunate enough to fall from the ledge of a cinder cone into a pool of magma?

    Zula110100100 - Say that the surface layer has not reached a temperature in which it is able to cool sufficiently?

    In general, some math would be dynamite. Like, the force it takes to break the surface tension of water. I can make assumptions from there...
  6. Dec 10, 2011 #5
  7. Dec 10, 2011 #6
    Zula110100100 - I was curious as to what applied force would break the surface tension of water? Maybe even a known equation that could apply would be dynamite? I do thank you for your input. I'll try to apply it...
  8. Dec 10, 2011 #7
    I'm also confused as to your notation. because 72.8 mN/m = 72.8N. Is this the required force in order to breach the surface tension?
  9. Dec 10, 2011 #8
    LOL, I'm an idiot. I got you man. Thanks Zula!!!
  10. Dec 10, 2011 #9


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    Staff: Mentor

    What's it matter how you got there--whether through taking a tumble, or being pushed? In either case, it's curtains!
  11. Dec 10, 2011 #10
    Well, it doesn't matter how one would fall.

    What would matter is how the question is interpreted though. And, I don't feel as though you're understanding the question correctly, NascentOxygen. It's neither an archaeological question, nor is it anthropologic. Rather, it's a question of whether or not one would sink if they were unfortunate enough to fall from the edge of a volcano into its magma pool.
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