本题目来源于试卷: Typical Forces，类别为 美国物理杯赛(Physics Bowl)
[单选题]
16.10: A person wishes 2i/ia(ct 8mdm rjx;t7 to acceleratyg+,j pq0 (o5zy8hl95h kbxcg e an object upward uniformly. Which one of the following choices must be true of the force F, provided by the person onto the object? W represents the magnitude of the gravitational force acting on the object. Ignore any effects of the air or o yyh5z+ gh08klgc, 9jqb(o 5pxf the Earth’srotation.
A. $F $= W
B. $F$ ≥ W
C. $F$ > W
D. $F$ ≥ 2W
E. $F $> 2W
参考答案: C
本题详细解析:
暂无
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