Need help on difficult Newton's First Law Question

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SUMMARY

The discussion revolves around a physics problem involving Newton's First Law, where Robin, with a mass of 45.0 kg, hangs from a rope that is 17.0 m long and spans 13.0 m between two buildings. The user seeks to determine the tension in the rope when equilibrium is established, utilizing the force of gravity (441 N) and the relationships between horizontal and vertical components of tension. The solution involves breaking down the problem into smaller parts, using trigonometric functions to find the angle of tension, and applying the equation T=ma to calculate the tension.

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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.
 
Last edited:
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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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