Help finding radius for the torque

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The discussion focuses on finding the radius for torque in a physics problem involving a beam and a cable. The radius is defined as the distance from the pivot point to where the force acts, which is identified as L. There is confusion about the relationship between the tension in the wire and the torque on the beam, with clarification that the force must act directly on the beam. The conversation highlights the use of trigonometry, specifically the sine function, to relate the sides of a right triangle formed in the scenario. Ultimately, the correct understanding of the geometry and forces involved leads to the proper application of torque calculations.
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Homework Statement


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Homework Equations


Torque = Force * radius * sin(angle)


The Attempt at a Solution



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I am trying to find the radius for the torque of the cable, but I can't seem to use any trig to solve for that side in terms of L.
 
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The radius is L,
you do not need any trigonometry.
remember, radius (when referring to torque) is defined as the distance from the pivot point to the point that the force is acting on - in other words - L.
 
The pivot point to the point that the force is acting on is marked in my diagram by 'R'. I don't see how R = L
 
The wire is pulling on the beam with a tension, this is the force in question. The point that you have marked as the point that the force is acting upon is on the wire itself. In order to cause a torque on the beam the force must be acting on the beam itself, not the wire.
 
I don't understand what you are saying. The force of the Tension is acting on the beam. The axis of rotation is the hinge. So, we need the distance from the Tension to the axis of rotation. To do that, we use the perpendicular distance created from the axis of rotation to the Tension. Isn't that what we want?
 
You have a right triangle where L is the hypotenuse and R is the side opposite the 30-degree angle. What trig function relates side opposite and hypotenuse?
 
Ah, I see the sine function now. Thanks
 

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