Find the Optimal Cut Point on a Hanging Thread

  • Thread starter Thread starter deepansu sharma
  • Start date Start date
  • Tags Tags
    Cut Point Thread
AI Thread Summary
The discussion centers on the optimal point to cut a vertically hanging thread with weights attached. It is suggested that cutting the thread near the ceiling, where the tension is greatest, would be the easiest option. This is based on the premise that higher tension makes the thread more rigid and less flexible, thus requiring less effort to cut. Participants agree that any section of the thread below the first weight experiences less tension, making it more difficult to cut. The consensus is that the top of the thread is the most advantageous point for cutting due to the increased normal strain, which causes the thread to elongate and thin out, facilitating the cutting process.
deepansu sharma
Messages
1
Reaction score
0
a weight is attatched midway to a thread which hangs vertically from a ceiling.another weight is attatched to the bottom end of the thread.where along the thread will it be most easy to cut and why?
 
Physics news on Phys.org
What's your initial guess (and why)?
 
I would say at the top, near the point the thread is attached to the ceiling. Why?, because at that point there is the greatest amount of tension on the thread, which makes it easier to cut.
My thoughts anyway.
 
I would say that your initial guess is correct, because any part of the thread below the first weight does not experience tension from that weight.

This is assuming it is easier to cut if it is more tense, which I think is a fair assumption.
 
I would say anywhere between the ceiling and the first weight.
regarding the assumption of higher tension = easier to cut, I would agree; it would flex less as the cutting object pressed against it
 
The top of the thread due to it having the highest normal strain (change in shape and volume), the thread would elongate and become thinner allowing less work to be done to cut the thread.
 
Last edited:
The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
Thread 'Beam on an inclined plane'
Hello! I have a question regarding a beam on an inclined plane. I was considering a beam resting on two supports attached to an inclined plane. I was almost sure that the lower support must be more loaded. My imagination about this problem is shown in the picture below. Here is how I wrote the condition of equilibrium forces: $$ \begin{cases} F_{g\parallel}=F_{t1}+F_{t2}, \\ F_{g\perp}=F_{r1}+F_{r2} \end{cases}. $$ On the other hand...
Back
Top