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Immovable Object vs Unstoppable Object

  1. Oct 22, 2015 #1
    Admit it. It's a pretty dang hard question, but here it is compressed down.

    So theoretically it's impossible to have either one, but never mind that. A immovable object has to be an object that cannot have its own speed or velocity changed, so it is an object that cannot be accelerated, since it cannot be moved from Point A to Point B, and the only way to get there is to accelerate or move.

    What about an unstoppable object? An unstoppable object is an object that cannot have its velocity or speed changed, so it would also be a object that cannot be accelerated, because if it's moving at 100 miles per hour, it will stay moving at a 100 miles per hour, and if it is moving at 1 mile per hour, then it will stay moving at 1 mile per hour. (If an unstoppable object did exist, we can harvest infinite energy, and break the second law of thermodynamics.)

    One other thing before we get to the answer, a immovable object is a object with infinite mass! F=MxA

    So now, what would happen if they collided with each other? My consensus with my other friends, and also Google is that a large explosion would happen.

    (Correct me if I'm wrong, I'm not the best with science)
  2. jcsd
  3. Oct 22, 2015 #2


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    Science Advisor

    As you said, both of these objects cannot exist. So your question boils down to, "If the laws of physics do not apply, what do the laws of physics say would happen?" Since you are throwing the laws of physics out the window, you can say anything you like about what would happen. But it is not a scientific answer.
  4. Oct 22, 2015 #3


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    Welcome QP,

    No questions or discussions are allowed in this section, this is Introductions Only. Please post your question in the proper forum after you read our rules for what is allowable.

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