Falling stick with weight on the end

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AI Thread Summary
The discussion revolves around a physics problem involving a massless stick with a 20kg weight at its end, which falls when touched. Participants express frustration over the lack of clear guidance in the class and the absence of a textbook. Key points include the need for clarification on whether there is friction at the base of the stick, as this significantly affects the problem's complexity. Without friction, the solution is straightforward, while the presence of friction complicates the calculations. The conversation highlights the challenges of understanding dynamics in this context.
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Homework Statement



There's a stick with a weight at the end standing straight up and I touch it slightly so it falls over. The stick is massless, the weight is 20kg and the length of the stick is 0.5 meters. How long will it take for the weight at the end to hit the ground?

Homework Equations



ƩF=\frac{dp}{dt}
Ʃτ=\frac{dL}{dt}


The Attempt at a Solution



I don't even know where to begin with this one. This class is horrible. There's no textbook, just examples that aren't similar at all to the problems given on the homework.
 
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Hello, leroyjenkens.

Is any information given as to whether or not there is any slipping of the end of the stick that is on the supporting surface?

In accordance with the rules of this forum, you need to show some attempt at a solution before we are allowed to provide any specific help.
 
TSny said:
Hello, leroyjenkens.

Is any information given as to whether or not there is any slipping of the end of the stick that is on the supporting surface?

In accordance with the rules of this forum, you need to show some attempt at a solution before we are allowed to provide any specific help.

Thanks for the response.
 
Last edited:
Fwiw, if there's no friction it becomes trivial. If there is friction it becomes indeterminate.
 
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