本题目来源于试卷: Newton’s law of motion，类别为 美国物理杯赛(Physics Bowl)
[单选题]
02.40: A box with a m ;6teuy- ksy3 mvv-.nvx t54e;/mshio ass (rz im3 b*a ;-dxa0opyd1zg0 gec:/nuof 50 kg is dragged across the floor by a rope which makes an angle of 300 with the horizontal. Which of the foll 0yaa-u1dgx* ez;c gn0:ro p/( 3idbzmowing would be closest to the coefficient of kinetic friction between the box and the floor if a 250 newton force on the rope is required to move the crate at a constant speed of 20 m/s as shown in the diagram?
A. 0.26
B. 0.33
C. 0.44
D. 0.56
E. 0.77
参考答案: D
本题详细解析:
暂无
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