Tension and Centripetal Force in Circular Motion

AI Thread Summary
The discussion clarifies the relationship between tension in rope 2 (T2) and centripetal force in circular motion. It explains that the horizontal component of T2, represented as T2cos(theta), is indeed the centripetal force required for circular motion, equating to mv^2/R. The confusion arises from mistaking the tension itself for the centripetal force, but it is clarified that only the x-component contributes to the centripetal force. A visual aid helped participants understand this concept better. Overall, the key takeaway is that T2cos(theta) equals the centripetal force acting on the ball.
Lori

Homework Statement


upload_2017-11-4_20-55-16.png

Where does T2cos(theta) come from ? Isn't mv^2/R the centripetal force which is the tension of rope 2?

Homework Equations



Fc = mv^2/R

3. Solution

Wait! The horizontal component of the circle is the centripetal force? So that part is mv^2/R?

I got confused and thought the tension of rope 2 is actually the centripetal force. But if the x point of that tension is the centripetal force, i see how they got T2Cos

since cos(theta) = Xcomp/T2
i get cos(theta) = (mv^2/R)/T2

so that T2cos(theta)= (mv^2/R)[/B]
 

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Yes, the ball is moving in a horizontal circle as shown below. The centripetal force must point from the ball toward the center of the circle. You can see that the x-component of T2 is the only force acting on the ball in this direction. So, the centripetal force is T2cosθ.
upload_2017-11-4_20-43-59.png
 

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Likes Lori
TSny said:
Yes, the ball is moving in a horizontal circle as shown below. The centripetal force must point from the ball toward the center of the circle. You can see that the x-component of T2 is the only force acting on the ball in this direction. So, the centripetal force is T2cosθ.
View attachment 214370
Thank you. Your drawing really made sense of this all!
 
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