A figure skater rotating at 5.00 rad/s with arms extended has a moment of inertia of 2.25 kg ∙ m².If the arms are pulled in so the moment of inertia decreases to 1.80 kg ∙ m²,what is the final angular speed? A)2.25 rad/s B)4.60 rad/s C)6.25 rad/s D)1.76 rad/s E)0.810 rad/s

Question

Quizplus · Accepted Answer

Conservation of angular momentum states that the angular momentum of a system remains constant if no external torque acts on it. Therefore, initial angular momentum (Iω) is equal to final angular momentum (I'ω').

Iω = I'ω'

We can rearrange this equation to solve for the final angular velocity:

ω' = (Iω)/I'

Substituting the given values, we get:

ω' = (2.25 kg ∙ m2/s)(5.00 rad/s)/(1.80 kg ∙ m2/s)
ω' = 6.25 rad/s

Therefore, the final angular speed is 6.25 rad/s, which is choice C.

A Figure Skater Rotating at 5