Statics Problem: Weight Hanging from a Rope

AI Thread Summary
The discussion revolves around a statics problem involving a 50kg mass hanging from a pulley with a 1kg mass on the rope. The participant attempts to solve for the height change (H) of the 50kg weight using force equilibrium equations and a free body diagram. They express confusion about the equation "2*50sin(x)=1" and how it relates to the forces acting on the 1kg weight. Clarification is provided that the solution involves understanding the relationship between the change in length of the rope and the height change of the 50kg mass. Ultimately, the key takeaway is the connection between the angles and the lengths in the context of the problem.
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Homework Statement


Mass hanging from the pulley in 50kg, the mass on the rope is 1kg. Please see attachment for details. The answer will be in terms on L.


Homework Equations


The sum of the forces in the y-direction and x-direction are equal to 0.


The Attempt at a Solution


Adding the moments at the pulley and equating them to 0; we have that T=50.
Now a free body diagram of the second weight. 2*50sin(x)=1, sinx=(1/100)=H/X
X=(L^2+H^2)^(1/2), substituding this in (1/100)=H/X, and solving for H, I find H=L/100.
Which is not the answer I have in the solutions.
Any help will be greatly appreciated.
 

Attachments

  • prob1.png
    prob1.png
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  • staticproblem1.png
    staticproblem1.png
    8.1 KB · Views: 511
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Can you explain to me "2*50sin(x)=1"?
 
When I draw the FBD of the 1kg weight; I addthe forces in the y-direction
50*sin(x)+50*sin(x)=1
 
What is the answer that they give?
 
I have attached the solution. I cannot follow what they are doing; if anybody does please help.
 

Attachments

  • solutionprob5.png
    solutionprob5.png
    14.5 KB · Views: 530
The key here is that they are asking how much the 50kg weight will move up due to the 1kg weight. the Solution shows the change in length of the rope over the horizontal section, which is the same as the change in height of the vertical section, which is the same as the 50kg mass.
 
Ok, I understand that now. But I still don't get where the 50/L is coming from.
 
sin(tetha)=50/L
 
Ok got it, thanks for the explanation.
 
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