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Creative solution to a physics problem

  1. Jan 27, 2007 #1
    This was posted on digg and I don't remember seeing it on here, so i thought I'd share:

    http://www.robmonroe.net/upload/2007/1/24/elephantintheway.jpg [Broken]

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jan 27, 2007 #2
    "Does the object continue to move after it comes to a rest?"

  4. Jan 27, 2007 #3


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    Indeed the question is almost as dumb as the answer.
  5. Jan 27, 2007 #4

  6. Jan 27, 2007 #5
    I love it.
  7. Jan 27, 2007 #6


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    It could have been worded better do you not think?
  8. Jan 27, 2007 #7
    I'm surprised they'd give five points for the second part of that question. It's obvious by inspection. You read the word "frictionless", and the question answers itself.
  9. Jan 27, 2007 #8
    Whats wrong with the wording?
  10. Jan 27, 2007 #9
    Think like a normal person (i.e., one who does not recognize that it only comes to rest for an instant of time). Something that has come to rest has ceased moving. By definition, it will not be moving after it has come to rest.

    Interesting aside: the quickest way to reconcile the two perspectives is to point out there is no "after" associated with the rest in question. The time spent at rest is zero.
  11. Jan 27, 2007 #10
    The question is written the way it is to see who knows the material. If the question said, comes to a rest instantaneously, I think it would be obvious to everyone that its going to move again.
  12. Jan 27, 2007 #11


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    Would you expect five marks for answering no? Evidentally the person who completed the question thought this could be remedied :rofl:
  13. Jan 27, 2007 #12
    If you put no, you would get a zero. Elephants or not.
  14. Jan 27, 2007 #13
    Consider this, does this system ever come to a complete rest?

    No, it does not. So there can ONLY be one solution implied in the question the way it is written.
  15. Jan 28, 2007 #14

    Qns : What would happen if you connected several light bulbs in a series?

    Ans : Nothing, you didn't connect it to a battery.
  16. Jan 28, 2007 #15


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    Even old folks in a bank know that:

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