Need help with a pulley and tension problem

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    Pulley Tension
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Homework Help Overview

The problem involves analyzing a pulley system with two ropes, focusing on the tensions in the ropes and the angles involved. The original poster is attempting to find the tension in one rope and the angle associated with another rope's tension, while considering the forces acting on both a penguin and a pulley.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to find the vertical component of the tension in rope two and expresses uncertainty about the horizontal component and the angle theta. Some participants question the completeness of the force analysis in both the x and y directions, suggesting the need to consider all forces acting on the pulley and the penguin separately.

Discussion Status

The discussion is ongoing, with participants providing guidance on the importance of a free body diagram and clarifying the roles of the different forces. There is a focus on ensuring that all forces are accounted for in the analysis, but no consensus has been reached on the specific approach to take.

Contextual Notes

Participants note the need for clearer definitions of variables and the importance of distinguishing between the forces acting on the pulley and the penguin. There are indications that the original poster may have misunderstood the connections between the ropes and the objects they affect.

Scott McKinnon
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Homework Statement


https://imgur.com/KANlHh9
KANlHh9.jpg

The problem and my equation for finding the tension in rope one are shown in the image above. I am stuck on finding the tension for the horizontal component of the second rope's tension and finding the angle theta

Homework Equations


F=ma
F=T-W

The Attempt at a Solution


[/B]
To find the tension in rope 2 I have tried to find the vertical component first, here's a run-down of what I did.

Fy=T2y-Wy
ma=T2y-mg
0=T2y-mg (since the penguin is at rest a=0)
T2y=mg
T2y=6.00kg*9.8m/s^2
T2y=58.8N

And for the horizontal component, I think the equation would go something like this?

Fx=T2x?

For angle theta I need more than one component to solve for, so at this point I can't, but if I had the x and y compenents I could just use tan^-1 adj/opp.
 

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It is very hard to read your mathematical symbols. There's a guide for writing nicer mathematics using LaTex: https://www.physicsforums.com/help/latexhelp/

But you haven't considered all the forces in the x-direction and the y-direction. There are two objects of interest: the penguin and the pulley.

On the penguin, we have two forces: A rope pulling up, and gravity pulling down. So there is no x-component. The forces have to add to zero.

On the pulley, we have three forces: One rope pulling straight down. One rope pulling at an angle of ##30^o##. And one rope pulling at angle ##\theta##. So you need to figure out the forces in the x-direction and the forces in the y-direction separately.
 
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Likes   Reactions: Marco Noguez
It will be very usefull to draw the Force Body Diagram of the pulley and answer the following question: What do you know about each tension force (magnitude and angle)?
 
The problem I have with reading your attempt is that you have not defined your variables. Which are you thinking of as rope 2?
If you mean the one at an angle then, as @Marco Noguez hints, your mistake is thinking of that tension as acting directly on the penguin. That rope is not attached to the penguin. Treat the pulley and penguin separately.
 

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