A 0.75kg tether ball is attached to a 1.6m massless string. What is the minimum speed needed to keep the ball at a radius of 1.2m? If the radius was replaced with a string of the same length what would be the tension of each string if the ball's speed is 5.5m/s?(adsbygoogle = window.adsbygoogle || []).push({});

For part 1 I think the equation to use is T*cos(theta)=(m*v^2)/r. Now I'm stuck because I have two unknowns being the tension and the speed. I'm not sure but is T=(m*g)/sin(theta)?

For Part 2 I think it has something to do with adding the lengths of the rope.

Other than that I'm lost.

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# Uniform circular motion help

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