Need help on difficult Newton's First Law Question

AI Thread Summary
The discussion revolves around a physics problem involving tension in a rope when a character, Robin, is hanging from it. The original poster outlines the forces acting on Robin, including gravity and the tension components, while attempting to establish equilibrium. They express confusion over missing variables such as acceleration and the angle of tension but later indicate they figured out the process to solve the problem. Another participant points out that the question was posted in the wrong thread and suggests breaking the problem down into smaller parts for clarity. The conversation emphasizes the importance of using trigonometric functions and Newton's laws to find the solution.
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*Just noticed that I posted in the wrong thread. Sorry about that is there any way I can move it to the right thread?*

I have a difficult question and any help would be greatly appreciated. Here it is:
To keep Robin from being captured, Batman tosses him out a third storey window, knowing that 17.0 m rope hangs slack between hooks of equal height on adjacent buildings 13.0 m apart. Robin grabs the rope and hangs on a point 5.0 m from one end. Assuming that Robin's mass is 45.0 kg and the rope withstands the initial impulse, what is the tension in each part of the rope when equilibrium is established.

Ok we know fnet is 0. Therefore the sums of the forces vertically and the horizontally must equal 0. In this problem we have mass but we don't have acceleration of the force applied by Robin (variable is a) or the acceleration of the tension (variable is b). We don't have the angle of the tension (variable @) and we don't have the Force applied horizontally by Robin (Fa) or the Tension in the rope. We do have the force of gravity however (mg, 45*9.8 = 441N). I assume that :
Horizontally
fnet = Fa - Tcos@ (Horizontal component of tension)
Tcos@ = Fa
Tcos@ = ma
T = 45a / cos@

Vertically
fnet = Fg - Tsin@ (Vertical component of tension)
Tsin@ = Fg
Tsin@ = mg
T = 441N/sin@

Substitution:
45a/cos@ = 441/sin@
45asin@ = 441cos@
45asin@/cos@ = 441
45atan@ = 441
tan@ = 441/45a
@ = tan-1(441/45a)

That will give you angle if you can get a. I believe there is a way to get a from using the values given in the question (17m, 13m, 5m) or if not then there should be a way to get @ from the values given and then solve for a instead of @. Substitute @ back into one of the T equations to get T. As I said before any help would be greatly appreciated.
 
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Nevermind, I figured out the process to find the answer.
 


Hi there, I'm not sure if you're aware, but you have posted this question in the wrong thread. This thread is for general discussions and not for specific homework or problem-solving help. It would be best to post this question in a thread specifically dedicated to physics or Newton's First Law.

As for your question, I understand that it can be quite challenging. My suggestion would be to break down the problem into smaller parts and use the given information to solve for the unknown variables. For example, you can use the distance and the angle to find the length of the rope using trigonometric functions. Then, you can use that length and the given mass to find the tension in the rope using the equation T=ma.

I hope this helps and good luck with your problem!
 
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