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Angle of Repose

  1. Aug 15, 2014 #1
    What is Angle of repose? All I know is something related to the body on an inclined plane slipping or at rest. Can someone explain?
     
  2. jcsd
  3. Aug 15, 2014 #2

    Doc Al

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    Staff: Mentor

    It's the maximum angle of incline where an object can remain at rest without sliding down.
     
  4. Aug 15, 2014 #3
    @Doc Al , Thanks!
     
  5. Aug 16, 2014 #4
    It also used to refer to the natural angle ( above horizontal ) of the side of a cone shape of loose material poured directly from above ( ie a heap of coal )
     
  6. Aug 16, 2014 #5

    jim mcnamara

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    Ant lions also depend on the angle of repose when they dig pit traps for ants in sandy soils. Ant lions are not mammals, they are insects.

    http://en.wikipedia.org/wiki/Antlion

    Ants that enter the pit trap scramble with poor footing to escape, while the larvae at the bottom of the pit lobs grains of sand at the intended prey. Poor purchase results from the fact that the ant lion's trap walls are exactly at the angle of repose for the material. So the ant or other bug scrambling up the trap wall is at a huge disadvantage. The lobbing of sand grains further dislodges the trap wall grains above the scrambling ant.
     
  7. Aug 16, 2014 #6

    Doc Al

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    Yes, the term has multiple meanings. But the context of mechanics was clear.
     
  8. Aug 16, 2014 #7
    Ant lions being closer i presume.
     
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