Uniform centripetal acceleration

AI Thread Summary
The discussion revolves around calculating the centripetal acceleration and tension in a system where a 3.0 kg ball revolves uniformly in a circle on a frictionless surface. The ball is attached to a 1.40 m string and completes 2 revolutions per second. To find the centripetal acceleration, the formula ac = v^2/r is used, but the velocity needs to be determined first. The user expresses uncertainty about calculating velocity from the given parameters, specifically the distance covered in one revolution. The conversation highlights the need for clarity on how to derive velocity from the circular motion context.
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Homework Statement


A small ball with a mass of 3.0kg revolves uniformly in a circle on a frictionless horizontal surface. The ball is attached to a string of 1.40m to a pin set at center of circle. The object makes 2rev/sec.

a)find the centripetal accel
b)find the tension exerted on the string

Homework Equations



ac=v^2/r
Fc= ma=m(4pi^2r/T^2)
T= .5


The Attempt at a Solution


if its uniform wouldn't the Fc=FT(force of tension)
T would =.5 because 2 rev/1 sec?
I am not sure how to find centripetal accel because i do not know how to find the velocity unless i am missing something..
 
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If it makes one revolution and the string is 1.40 m, how much distance does it cover?
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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