Questions about circular motion/ centripetal acceleration/force

AI Thread Summary
A 20 kg ball in constant circular motion is analyzed for its velocity given a radius of 0.5 m and an angle of 10 degrees. The discussion highlights the forces acting on the ball, specifically centripetal force and gravity, with a total weight of 196 N. It emphasizes that centripetal force is not a separate force but the net force resulting from other forces, including tension. The conversation also touches on the importance of a free body diagram (FBD) to visualize the forces and their components. Understanding how these forces balance, especially with the angle involved, is crucial for solving the problem.
brittylaurel
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Homework Statement


a 20 kg ball attached to a string is moving in constant circular motion. if theta= 10 degrees and the radius of its circular path is 0.5 m, what is the ball's velocity?


Homework Equations


a(centripetal)=V^2/r


The Attempt at a Solution



As far as I got was F(net)=F(centripetal), then I was lost
 
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brittylaurel said:

Homework Statement




As far as I got was F(net)=F(centripetal), then I was lost

What forces are on your ball? (draw it and then an fbd)
 
Oh! The teacher told the class that there are only two forces acting on the ball. There is F(centripetal) and there is F(gravity) which is 196 N I got that from the information. What is an fbd?
 
brittylaurel said:
What is an fbd?

Free Body Diagram~ it's where you draw the object (or usually just a dot to represent it) and use arrows on it to represent the forces.
Also, the centriptial force is not a new force (the name is misleading), its the net force of a circular motion problem. Certain forces on the object (like weight, etc) cause the circular motion, which results in an overall net force that makes the object go in a circle. (circular overall net force = centripital force). So what forces make your object go in a circle?
 
brittylaurel said:
Oh! The teacher told the class that there are only two forces acting on the ball. There is F(centripetal) and there is F(gravity) which is 196 N I got that from the information. What is an fbd?

Yes, there's a weight component, and there's a centripetal force, but there's also tension. How can you relate these three?
 
brittylaurel said:

Homework Statement


a 20 kg ball attached to a string is moving in constant circular motion. if theta= 10 degrees and the radius of its circular path is 0.5 m, what is the ball's velocity?
It appears the string is at an angle...while another force is perpendicular to the object... If the object doesn't move up or down, doesn't that mean that something is balancing out the force? If so, how does a Force at an angle balance it out? (think vectors)
 
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