I am having a hard time defining theta in Torque=rFsin(theta)

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Theta in the torque equation Torque = rFsin(theta) represents the angle between the position vector (r) and the force vector (F). In the context of a pulley, the tension forces are tangential to the pulley, meaning they act along the circular path of the pulley. When a force is applied at the point of application, it is at a 90-degree angle to the radius drawn from the center of the pulley to that point. Therefore, for a pulley, theta is typically 90 degrees. Understanding this relationship clarifies the calculation of torque in rotational systems.
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Can someone dummify what theta represents in Torque = rFsin(theta)?

if my understanding of theta is correct for this problem theta would be 53 degrees.
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dadiezel07 said:
Can someone dummify what theta represents in Torque = rFsin(theta)?
In general, θ would be the angle between the position vector (r), which describes the point of application with respect to some axis, and the force vector (F).
if my understanding of theta is correct for this problem theta would be 53 degrees.
No. Assuming you are trying to express the torque on the pulley, realize that the tensions are tangential to the pulley.
 
Doc Al said:
No. Assuming you are trying to express the torque on the pulley, realize that the tensions are tangential to the pulley.

When you say they are tangential to the pulley, can you explain a little furthur.

Thats another subject I can't quite wrap my head around is the definition on tangential, is it the word to describe "linear" equations?

I have been continuing the subject without complete understanding of everything this is my attempt at understanding everything because my book does a horrible job.
 
dadiezel07 said:
When you say they are tangential to the pulley, can you explain a little furthur.
I mean that the line of action of the tension force (which is the line that the ropes make) is tangential to the circle that is the pulley. Which means that if you draw a radius to the point of application of the force, the force would be at 90° to the radius.
 
so in the case of the pulley will the theta angle always be 90 degrees?
 
dadiezel07 said:
so in the case of the pulley will the theta angle always be 90 degrees?
Yes.
 

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