# Thread: Mathematically proving "can't push on a rope"

1. ## Mathematically proving "can't push on a rope"

I know intuitively that if i hold a roll of rope in front of me and have one end of the rope draped over a pulley above my head, that if I try to push the rope over the pulley by unspooling the rope, it won't work because I can't push on a rope, but what is the math behind it? Is there a speed that the pulley can spin that will draw up the rope?

2. Google "Newtons laws of Gravity"

3. The Reason behind the phenomena is friction, the Newtons law of gravity said that every object is experiencing the Gravitation Force, push and pull and other forces

4. I see this problem similar to Euler's column buckling problem with a low modulus and high slenderness ratio.

5. Fluids are pushed all of the time. Ever seen a fire hose?

6. I suppose that Column Theory or Euler's formula could be used.. Both ends would be treated as pinned?

https://www.engineersedge.com/column...lumn_ideal.htm

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