本题目来源于试卷: Physics Unit6: Work and Energy，类别为 通用国际物理
[单选题]
You throw a ball straight up. w.n 9 jx(59yiff8 xjqaCompare the sign of the work done byz044v mx wcps *c9t4fjyxmn(9 gravity while the ball goes up with the sign of the work done by gravity while it goes 4jx wtm0 m zf94(cp*c49vsnyx down.
A. Work is + on the way up and + on the way down.
B. Work is + on the way up and - on the way down.
C. Work is - on the way up and + on the way down.
D. Work is - on the way up and - on the way down.
参考答案: C
本题详细解析:
暂无
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