Calculating Moment of Inertia: A Figure Skater's Finale

AI Thread Summary
To calculate the final moment of inertia of the figure skater, the conservation of angular momentum principle must be applied, which states that the initial angular momentum equals the final angular momentum. The initial angular momentum can be calculated using the initial rotation rate and moment of inertia, while the final angular momentum uses the final rotation rate. The skater's initial rotation rate is 1.14 revolutions per 1.86 seconds, converting to radians per second is essential for accurate calculations. The discussion highlights the need for proper unit conversion and the application of the angular momentum formula, emphasizing the importance of understanding the relationship between rotation rates and moment of inertia. The final moment of inertia can be determined once these calculations are correctly executed.
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Homework Statement



A figure skater during her finale can increase her rotation rate from an initial rate of 1.14 revolutions every 1.86 s to a final rate of 3.13 revolutions per second. If her initial moment of inertia was 4.46 kg*m2, what is her final moment of inertia?


Homework Equations





The Attempt at a Solution


I thought that I could use some type of mathematical relationship between the revolutions per second and the inertia. However, I am not getting the correct value. Any help will be appreciated. Thanks.
 
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Angular momentum is conserved.
 

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