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This a momentum and torque question.
Experiment I: One student sits on a stool that rotates freely. He holds a 5-kg mass in each hand. Initially, the student has an angular velocity of 5 radians/sec with his arms in his lap.
45) In experiment 1, with his arms outstretched, the student drops the weights. How can it be explained that the student's angular velocity does not change?
A. The center of mass does not change for the student, so angular momentum is constant.
B. The position of the weights does not impact angular momentum.
C. The falling weights continue to move in their circular pathway as they fall, so they retain their same angular momentum.
D. The weights are rotating in opposite directions after they are dropped.
I had used POE to get it down to A and B, and I chose A. I never fathom that C was an option because I thought they were asking about the student's angular velocity not the weights.
Can someone explain why my choices are wrong and why C makes sense? I don't understand their explanation. Thank you.
Experiment I: One student sits on a stool that rotates freely. He holds a 5-kg mass in each hand. Initially, the student has an angular velocity of 5 radians/sec with his arms in his lap.
45) In experiment 1, with his arms outstretched, the student drops the weights. How can it be explained that the student's angular velocity does not change?
A. The center of mass does not change for the student, so angular momentum is constant.
B. The position of the weights does not impact angular momentum.
C. The falling weights continue to move in their circular pathway as they fall, so they retain their same angular momentum.
D. The weights are rotating in opposite directions after they are dropped.
I had used POE to get it down to A and B, and I chose A. I never fathom that C was an option because I thought they were asking about the student's angular velocity not the weights.
Can someone explain why my choices are wrong and why C makes sense? I don't understand their explanation. Thank you.