题目
题目

SPHY001 Practice Quiz - Unit 10 | LA050

单项选择题

An ice skater performs a fast spin by pulling outstretched arms down and close to her body. What happens to her kinetic energy with respect to the axis of rotation?  

选项
A.It doesn’t change
B.It increases
C.It decreases
D.It depends how fast she rotates
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标准答案
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思路分析
In this scenario, the ice skater converts potential muscle work into rotational kinetic energy as she changes her moment of inertia. Option 1: 'It doesn’t change' would be false because angular momentum is conserved in the absence of ex......Login to view full explanation

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