Simple Vector Problem - Cable Tensions

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Homework Help Overview

The problem involves a traffic light weighing 125 N that is suspended by two cables, requiring the determination of the tensions in these cables while the system is in equilibrium. The context is rooted in vector analysis and equilibrium conditions.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to define the tensions in the cables using vector notation and equilibrium equations. Some participants suggest balancing forces horizontally and vertically, while others discuss decomposing the forces into components.

Discussion Status

The discussion is ongoing, with participants exploring different methods to approach the problem. Some guidance has been offered regarding the need to balance forces, but there is no explicit consensus on the steps to take.

Contextual Notes

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Homework Statement



A 125 N traffic light is hanging from two flexible cables. The magnitude of the force that each cable applies to the 'eye ring' holding the lights is called the cable tension. Find the cable tensions if the light is in equilibrium.

I have attached a scan from the textbook which contains a diagram.

Homework Equations



Not sure exactly what equations are there, except pythagoras theorem for magnitude, SOH-CAH-TOA.

The Attempt at a Solution



I assigned the first tension cable (left one) as vector a, the second one (right one) as b and the traffic light as g.

a = (x1cos150, y1[/SUB/sin150)
b = (x2cos45, y2[/SUB/sin45)
g = (0, -125)

And I think: a + b + g = 0

Answer is: T1 = 125([itex]\sqrt{3}[/itex]-1) N; T2 = 87.5(3[itex]\sqrt{2}[/itex]-[itex]\sqrt{6}[/itex]) N.

Thank you!
 

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There's nothing attached to the message.
 
That's weird, I remember the image showing up during the preview. I re-attached it though.
 
You have to first balance the horizontal forces (left-right) to make them zero, then you calculate the vertical ones.
 
Umm...how do you do that?
This is actually from a math course.
 
Well, decompose the force of each cable into an horizontal and a vertical component.
 

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